How do I find x? Exponential equation with two different bases. Reddit precalculus r/Homworkhelp

Learn how to solve an exponential equation with two different bases. We will go over two ways. Be sure to remember the rules of exponents and logarithms. Here's a video with 10 examples of solving exponential equations, from basic to hard!: • Solving exponential eq...
This question is from Reddit r/Homeworkhelp / ik4bneuk6y
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#math #algebra #mathbasics

Пікірлер: 564

  • @bprpmathbasics
    @bprpmathbasicsАй бұрын

    Here's a video with 10 examples of solving exponential equations, from basic to hard!: kzread.info/dash/bejne/fWx3s8SMdJzdmdY.html

  • @reesetit
    @reesetit3 ай бұрын

    I'm just impressed how you write with two different colors in one hand.

  • @dddaaa6965

    @dddaaa6965

    3 ай бұрын

    Imagine now how sex

  • @loser1233

    @loser1233

    3 ай бұрын

    it's like using chopsticks

  • @yafmaverick

    @yafmaverick

    3 ай бұрын

    You must be special

  • @viCuber

    @viCuber

    3 ай бұрын

    Lmao exactly the same I commented about two weeks ago

  • @kajalde3071

    @kajalde3071

    2 ай бұрын

    I'm impressed that you do that with two hands

  • @daenerystargaryen
    @daenerystargaryen2 ай бұрын

    I don't know why I'm watching this at 5AM since I'm a physicist doing PhD in neurophysics and computational neuroscience, but I thoroughly enjoyed this. 10/10. Younger generations are so lucky that they have someone like you explaining maths. Hopefully they'll know how to appreciate it and not waste their brains away on TikTok...

  • @scienceislove2014

    @scienceislove2014

    2 ай бұрын

    Woah..sounds interesting.. can you elaborate like what things you study and tools you use?

  • @johnmarcusengreso8273

    @johnmarcusengreso8273

    2 ай бұрын

    Ill take it as a compliment mr neurophysics man Im a 10th grader that likes math

  • @J0EB0B555

    @J0EB0B555

    2 ай бұрын

    I'm a physics major as well but haven't taken a math course in a while. He's really helpful for keeping all the concepts fresh in my brain.

  • @IskzenMisishuw

    @IskzenMisishuw

    2 ай бұрын

    Yes brother true

  • @antonioruelas8902

    @antonioruelas8902

    Ай бұрын

    Physics undergrad here, this man (and Organic Chemistry tutor) saved me during calc 2

  • @keroro407
    @keroro4072 ай бұрын

    "How to find X?" Bro, it's time to move on. Your X doesn't care about you anymore.

  • @bprpmathbasics

    @bprpmathbasics

    2 ай бұрын

    y?

  • @TheOnlineTurtle

    @TheOnlineTurtle

    2 ай бұрын

    @@bprpmathbasics😂 thats good

  • @r0N1n_SD

    @r0N1n_SD

    Ай бұрын

    Lol. Bro got owned by Math😂

  • @stalincomrade1867

    @stalincomrade1867

    Ай бұрын

    Don't you z how pointless it is?

  • @Taokyle

    @Taokyle

    Ай бұрын

    lol

  • @MC-qm5jn
    @MC-qm5jn3 ай бұрын

    i took precalc 4 years ago and was arbitrarily recommended this video yet I still feel compelled to do the homework this man has given

  • @xxxBradTxxx

    @xxxBradTxxx

    Ай бұрын

    I took it 15 years ago and I still watch these videos because it feels like a waste of effort to learn all of that an forget it. 🤷‍♂️

  • @Gamert80
    @Gamert803 ай бұрын

    I'm in 10th grade, so whenever he says "let's use this rule" I'm just like "uh huh" Edit: it's crazy how different some curriculums are in other countries.

  • @diewand5442

    @diewand5442

    3 ай бұрын

    We learned the logarithm in 10th grade😅 (Germany)

  • @AutoFun_

    @AutoFun_

    3 ай бұрын

    Why are u here?

  • @Gamert80

    @Gamert80

    3 ай бұрын

    I enjoy watching advanced math, even if I don't understand it fully.

  • @Gamert80

    @Gamert80

    3 ай бұрын

    @@diewand5442 I'm only half way through the year so I may learn it soon.

  • @aaryan8104

    @aaryan8104

    3 ай бұрын

    SAME FROM INDIA BTW

  • @jordananderson2728
    @jordananderson27283 ай бұрын

    To expand it, you use change of base to get log(96)/log(2/3). When dividing a logarithm, of course, you subtract the log of the denominator from the log of the numerator, which gives log(96)/(log2-log3). We can take the prime factors of 96: 3 and 2⁵, to get log(3•2⁵)/(log2-log3). With multiplication of logarithms, you add the logs of the multiplicands, so (log3 + log(2⁵))/(log2-log3). Finally, with exponentiation, you multiply the logarithm of the base by the exponent, which gives (log3 + 5log2)/(log2-log3).

  • @jordananderson2728

    @jordananderson2728

    3 ай бұрын

    I should have used ln rather than log, but I'm so used to using log for change of base that I just did that by default. It works the same either way (:

  • @GreggRomaine

    @GreggRomaine

    3 ай бұрын

    Nicely done, thanks for doing my homework!

  • @paratoxicalcapybara3939

    @paratoxicalcapybara3939

    3 ай бұрын

    you can just use laws off exponents bcuz that seems easier. then you log it at the end for answer turn 2^(x-5) into 2^x*2^-5 and turn 3^(x+1) into 3^x*3. an example of this is (3^2)*(3^2)=3^4 expand into 1/32(2^x)=3(3^x) do some division to isolate x as much as possible. 3/(1/32) = 96 or (1/32) = 1/96. End up with 2^x=96(3^x) or 1/96(2^x)=3^x x root everything. 2=xroot(96)*3 or xroot(1/96)*2=3 more division to isolate x. 2/3=xroot(96) or 3/2=xroot(1/96) put everything to the x power. (2/3)^x=96 or (3/2)^x=1/96 now log bcuz inverse of exponential to finnaly actually isolate x. log(base(2/3)) of 96 = x or log(base(3/2)) of 1/96 = x x= ~-11.25

  • @Kasakuja

    @Kasakuja

    3 ай бұрын

    well, how do you get from log(96) ---- log(2/3) to ln(96) --- ln(2/3) ?

  • @TheWatch1

    @TheWatch1

    3 ай бұрын

    Log(96)/Log(e) is ln 96. Divide by log e in Nr and Dr

  • @zuhakhalid4900
    @zuhakhalid49003 ай бұрын

    That was a really good explanation! Thank you for explaining so clearly! 👏

  • @lucsas9277
    @lucsas92773 ай бұрын

    the second option is always what comes to my mind first, i find it way easier and more intuitive, but ive forced myself doing the natural base method too cuz you have to know them both imo

  • @riccardodellorto4267

    @riccardodellorto4267

    3 ай бұрын

    I do the complete opposite: whenever I see an x as an exponent, I use ln, because the calculator can eventually solve any monstrosity I type in as long as there are numbers 😂 Bringing down the x is my number one priority 🫡

  • @Dr.Insomniac.
    @Dr.Insomniac.Ай бұрын

    So I'm a 3rd year medical student watching this video and I dearly enjoyed it. Its like going down the memory lane. Really smooth teaching. Kudos to you..❤

  • @akifhossain5122
    @akifhossain51222 ай бұрын

    I have a Zoology exam tomorrow. It's 3am. 10/10

  • @ominious7082

    @ominious7082

    19 күн бұрын

    Yo how did it go? 😂

  • @utkarshjain861

    @utkarshjain861

    2 күн бұрын

    So, how did it went?

  • @shrekyboi4776
    @shrekyboi47763 ай бұрын

    I solved it slightly different. I recognized that 3^(x+1) can be rewritten as [(1.5)(2)]^(x+1), which can be expanded as 1.5^(x+1) 2^(x+1). This is very helpful as it gives us an exponential of base 2 on both sides of the equation, which allows us to cancel out the x on the left side through exponent division rule. The full solution is below: 2^(x-5) = 3^(x+1) 2^(x-5) = [(1.5)(2)]^(x+1) 2^(x-5) = 1.5^(x+1) 2^(x+1) 2^(x-5)/2^(x+1) = 1.5^(x+1) 2^(-6) = 1.5^(x+1) Now we only have a single x variable to deal with, so we could simply apply log to both sides and isolate for x log[2^(-6)] = log[1.5^(x+1)] (log[2^(-6)]/log[1.5]) - 1 = x -11.257 = x

  • @user-lb3ex6yh9u

    @user-lb3ex6yh9u

    3 ай бұрын

    Well done

  • @praneel1059

    @praneel1059

    3 ай бұрын

    when i saw the thumbnail i guessed that since 2^(x-5) = 3^(x+5) we can do something like 2^(x-5) . 1/ 3^(x+5) then 2^(x-5) x (3^(x+5)) ^(-1) and go on i guess . Btw im in ninth grade so i have no clue about what ln is

  • @hridayjr6580

    @hridayjr6580

    2 ай бұрын

    nice is the antilog required or this is it.

  • @scorpio9711

    @scorpio9711

    2 ай бұрын

    ln is called natural log, where the base is 'e' which is called eular constant. BTW which country do you belong to

  • @kashi2928

    @kashi2928

    2 ай бұрын

    I got that too, thanks for making me feel like I wasn't alone 😂

  • @brown_bread_
    @brown_bread_2 ай бұрын

    I gave up on maths nearly 7 years ago in school. In my post graduation i watch this and feel my antipathy towards the subject reduce a little. Thanks

  • @CuriousCyclist
    @CuriousCyclistАй бұрын

    Thank you for taking the time to make this video. Much appreciated. ❤

  • @bprpmathbasics

    @bprpmathbasics

    Ай бұрын

    Glad to help! 😃

  • @sachinjain5367
    @sachinjain53673 ай бұрын

    I Just Saw the Thumbnail And Thought " Ehhhh That looks Ez Lets Just Do It " Only to waste 30 mins And Find Out It Have Logarithm Which I Havent Studied😂

  • @ankitbhadra4105
    @ankitbhadra4105Ай бұрын

    to think that I knew all those formulas you used and wrote on right side but still I didn't knew how putting them together will get me the answer. Thanks a lot. Any advice on how I can solve this thing of not knowing when to put and which things together to solve questions like this ?

  • @oreivankovic7318
    @oreivankovic73183 ай бұрын

    bro fumbels my brain and proceedes to say:"but, here is a prettier way to do it"

  • @CST1992

    @CST1992

    2 ай бұрын

    C'mon dude, if you know the rules of log this is a pretty simple problem.

  • @frostcrackle2374

    @frostcrackle2374

    Ай бұрын

    So maybe they don't know logarithm rules yet. C'mon dude if you can calculate a Hohmann Transfer, this is a pretty simple problem. ​@@CST1992

  • @celoreads

    @celoreads

    Ай бұрын

    @@CST1992 if we know the rules of log we wouldnt be here for an explanation now would we? lmfao

  • @CST1992

    @CST1992

    Ай бұрын

    @@celoreads you don't know what log is but you are on a calculus video? Go back to high school... "lmfao"

  • @abcdqwerty3562

    @abcdqwerty3562

    29 күн бұрын

    @@CST1992Do you not realise that the title of the video literally says precalculus?

  • @ToddKunz
    @ToddKunz2 ай бұрын

    You are so talented in teaching. Thank you for your wonderful videos.

  • @javify18
    @javify183 ай бұрын

    Very first approach of solving exponential equations is using logarithms.

  • @jameshy69
    @jameshy692 ай бұрын

    australian here, i used my calculator. ive only seen the thumbnail and came straight here. the answer i got was (-ln(96))/ln(3/2) or approximately-11.257 edit: finished the video now and checked those two values of x. both were equal to my above answer. very nice 👍

  • @ryg4493
    @ryg44933 ай бұрын

    Bro I'm in 10th grade and I reached (2/3)^x = 96 and was like, "Now what?". Then I realised "Oh, this is out of bounds" 💀💀💀💀

  • @imagod4796

    @imagod4796

    3 ай бұрын

    this is 9th grade in Germany

  • @ryg4493

    @ryg4493

    3 ай бұрын

    @@imagod4796 I thought Asia had the toughest math.....

  • @exip9288

    @exip9288

    3 ай бұрын

    @@imagod4796 This is 12th grade in Turkiye (I know it sucks dumb education system) , but I learned it way before because of calc bc.

  • @bruv4266

    @bruv4266

    3 ай бұрын

    @@exip9288 We all have shitty educations, here in Romania we learn calculus in 11th grade to 12th grade, they should have system of education like USA, this is where the people can learn it well, we have short time in school but too much to learn, cause it's not just math, its also other lesson that it supposed to be in college like physics, chemistry, etc.

  • @NotKartikeySingh

    @NotKartikeySingh

    3 ай бұрын

    bro but if u have studied from better school in 9th they would have taught u (in india)

  • @DA-gs4gu
    @DA-gs4guАй бұрын

    I would consider simplify it with log to the base 10 which yields the same answer as the answer you obtained. We could write it as, X-5log(2)=X+1log(3) Which on further simplification can provide, x= -6.58/0.58= -11.3 And the answer you obtained at the end, log (base)2/3 (96)= -11.26 (approx) I feel its less hectic

  • @TheLobsterCopter5000
    @TheLobsterCopter50002 ай бұрын

    I'm not sure which form of the result I prefer. The first form uses ln rather than a logarithm with an awkward base, but the second one looks neater.

  • @imran_sholeh
    @imran_sholehАй бұрын

    I have a question sir. Why we need to use ln instead of log, or we can use which?

  • @user-lw5wi8su7r
    @user-lw5wi8su7r2 ай бұрын

    I did it the first way, but with logbase2 instead of ln. Thanks for the video!

  • @Christopher-vw5ju
    @Christopher-vw5ju2 ай бұрын

    Could you please make a video on how to find values with decimal exponents Example) (15) ^1.4

  • @btsmochimi7924
    @btsmochimi79243 ай бұрын

    Love this reddit series

  • @christopher8504
    @christopher85042 ай бұрын

    Another way to do it like the first method that isn't exactly any faster but came to me is: once we have (x - 5) ln(2) = (x + 1) ln(3), (eq. 1) we can build h(x)=(x - 5)/(x + 1) = ln(3)/ln(2), (eq. 2) which will have the same solution despite the domain changing a bit, since the solution isn't near -1. and separate that into two equations: f(x₁)=(x₁ - 5) = ln(3) g(x₂)=(x₂ + 1) = ln(2) so solution x (to h) will be formed by solutions x₁/x₂ to f,g respectively. Which, is a linear system. now we can produce a matrix: [[1, -5, ln(3)], [1, 1, ln(2)]] which we partially row reduce to [[6, 0, 5ln(2) + ln(3)], [0, 6, ln(2) - ln(3)]] recombining, since solution to h is solution to f over solution to g, the 6's cancel and we have: x = (5ln(2) + ln(3))/(ln(2) - ln(3)) which is also the solution for eq.1 I know written out this seems long, but it went a lot faster in my head. A lot of the steps here would be incorrect if I didn't explain them carefully. Also it would probably take longer to row reduce than just doing the algebra but ¯\_(ツ)_/¯ let me know if I did anything illegal math manipulations

  • @argonwheatbelly637

    @argonwheatbelly637

    2 ай бұрын

    I like it. 😊 It reminds me of when I use Synthetic Division to blitz through some polynomial division by hand.

  • @nicholasscott3287
    @nicholasscott32873 ай бұрын

    Immediate reaction is "x is not positive integer, because 2 and 3 are prime, so the prime factorisation of 2^i will never equal that of 3^j, where i and j are any positive integer".

  • @tobybartels8426

    @tobybartels8426

    3 ай бұрын

    This also works for negative integers, even for non-zero rational numbers. So the only possible rational solution would be if both exponents are zero (at the same time, which is not possible in this case).

  • @deltalima6703

    @deltalima6703

    3 ай бұрын

    You never know if x is a quaternion or is mod |p| or whatever in these dumb questions.

  • @General12th

    @General12th

    3 ай бұрын

    ​@@deltalima6703This is an algebra channel, not a calculus or analysis channel, so don't overthink it.

  • @jackposiedonforever7774

    @jackposiedonforever7774

    3 ай бұрын

    Correct

  • @cristalmyth09
    @cristalmyth09Ай бұрын

    I learned this a while ago, i kinda just forgot about it. So yeah, im greatful for the recap

  • @joelmiller3067
    @joelmiller30673 ай бұрын

    Thank you sir ❤

  • @bprpmathbasics
    @bprpmathbasics2 ай бұрын

    Try this next: 2^x=5^(x+2) Answer here: kzread.info/dash/bejne/iYBh0NKMddy8hNI.html

  • @imabiggoofy

    @imabiggoofy

    2 ай бұрын

    bro really out here assigning hw 💀 (I'm in 8th grade, i dont know shit)

  • @FloraLemonYT

    @FloraLemonYT

    2 ай бұрын

    I actually learned this last unit. 2^x=5^(x+2) xln2=xln5+2ln5 xln2-xln5=2ln5 factor out x x(ln2-ln5)=2ln5 x=2ln5/(ln2-ln5) I’m not sure if there’s a better way to simplify it

  • @IamFlaem1

    @IamFlaem1

    2 ай бұрын

    x=log2/5(25)

  • @Neet_mbbs.0907

    @Neet_mbbs.0907

    Ай бұрын

    ​@@FloraLemonYTThat's correct! 👍

  • @vandernight1220

    @vandernight1220

    Ай бұрын

    I mean: (X-5)log2 = (x+1)log3 … -> x = (5log2 - log3)/(log2 - log3) is just way less complicated than the methods shown, at least this is the standard method in uk

  • @siddheshvispute2315
    @siddheshvispute23153 ай бұрын

    Actually the equation becomes easy, when you use log in exponential problems. Thanks ❤🇮🇳

  • @slulzspot7583

    @slulzspot7583

    3 ай бұрын

    मुझे भी equation देख के वही लगा।

  • @partelthales
    @partelthales3 ай бұрын

    Hey there! Could I just use Log10 instead of Ln, so that the first equation would be Log(2^(x-5)) = Log(3^(x+1))? It comes more naturally to me this way and, knowing that it's added to the two sides of the equation, seems like both ways would be accepted. Is that right? Thanks!

  • @edwardSteadyHands

    @edwardSteadyHands

    2 ай бұрын

    Yes doesn't make any diff which base you take

  • @sidhaarthnair8368
    @sidhaarthnair8368Ай бұрын

    I wasn't taught log at school at all. I had to look it up online. Even though we hadn't had proper knowledge about log we still have to use in calculus

  • @Roro-ej7ke

    @Roro-ej7ke

    Ай бұрын

    Lol same💀

  • @Shiva-xp4wv
    @Shiva-xp4wv24 күн бұрын

    Bro i am a Engineering major why did i click on this video

  • @actionj761

    @actionj761

    14 күн бұрын

    Same thing im like do i really have nothing better to do than to glance at my freshman year history 😂😂

  • @Matthew-px4vu
    @Matthew-px4vu3 ай бұрын

    I solved it in a similar way somewhat. Started with taking the natural log but instead grouped terms like: (x-5)/(x+1)=ln3/ln2 (x+1-6)/(x+1) = ln3/ln2 1-6/(x+1)=ln3/ln2 (x+1)=-6/(ln3/ln2-1) x=-6/(ln3/ln2-1)-1 x~=-11.257

  • @nothingbutpain863

    @nothingbutpain863

    Ай бұрын

    That seems more intricate.

  • @lukaskamin755
    @lukaskamin7553 ай бұрын

    you can do backwords in 6:00 ONLY IF a and b are both positive (theoretically a can be 0 , but it's a disputable question)

  • @amanda-we9fv

    @amanda-we9fv

    3 ай бұрын

    что?

  • @lukaskamin755

    @lukaskamin755

    3 ай бұрын

    @@amanda-we9fv now it's correct. I mean you can't do backwards if a and b are both negative ,roots of a and b won't be defined then, while root of ab will be defined

  • @arcturusgd

    @arcturusgd

    2 ай бұрын

    In this case it is. If it is positive that means a,b ∈ N

  • @leviackermann4080
    @leviackermann40803 ай бұрын

    Wow that is much easier than i thought

  • @Sayan_0-0_
    @Sayan_0-0_Ай бұрын

    It’s 4:20 am right now and I have no idea why I’m watching this at this time. I told mom to call me at 8 and wake me up. I guess now I have a solid reason to tell her why i was awake.

  • @sahhanaaa
    @sahhanaaa2 ай бұрын

    guys we can solve it in another way too. what i did was this: i took log on both lhs and rhs. so the exponent comes down and the equation becomes like such (x-5)log 2=(x+1) log 3 now we know log 2= 0.3010 and log 3=0.477 so we just use those values in the equation (x-5)*0.3010=(x+1)*0.477 0.3010x-1.505=0.477x+0.477 this becomes -0.176x=1.982 x=1.982/-0.176 x=-11.26

  • @user-bg9xo3ub8q

    @user-bg9xo3ub8q

    2 ай бұрын

    It was not log tho. It's was ln.

  • @sahhanaaa

    @sahhanaaa

    2 ай бұрын

    @@user-bg9xo3ub8q works w log too

  • @Gaysandthechaos

    @Gaysandthechaos

    2 ай бұрын

    ​@@user-bg9xo3ub8qyeah you'd have to multiply it with 2.303 to convert ln to log That'd be easier ig

  • @user-bg9xo3ub8q

    @user-bg9xo3ub8q

    2 ай бұрын

    @@Gaysandthechaos yes

  • @nothingbutpain863

    @nothingbutpain863

    Ай бұрын

    ​@@user-bg9xo3ub8q, in this scenario, either 'ln' or 'log' is acceptable. This is because the bases of logarithms would get cancelled in the process as long as the bases are the same.

  • @heyyythereitsjulie
    @heyyythereitsjulieАй бұрын

    In the first example, could you have used log instead of ln? When to use log vs ln?

  • @nothingbutpain863

    @nothingbutpain863

    Ай бұрын

    In this scenario, there is not difference. The only situation requiring 'ln' is when the base of an index is 'e'.

  • @nothingbutpain863

    @nothingbutpain863

    Ай бұрын

    Also, ln(x) is equivalent to log(e, x).

  • @JustMe-pd8zm
    @JustMe-pd8zm24 күн бұрын

    Even cooler is the fact that if you simplify the first answer they would be the same(I don't know if I'm right to be honest but iirc then that's cool) For example the numerator (ln 3 + 5 ln 2) can be rewritten as: ln 3 + ln 2⁵ or ln 3 +ln 32 Which is equal to ln (3•32) or ln 96 And the denominator can be rewritten as ln (2/3). Which means the equation can be written as [ ln 96/ln (2/3)] which is just equal to the second answer log base 2/3 of 96!

  • @prelude8975
    @prelude8975Ай бұрын

    I'm an international relations major and somehow watched this whole video and nodded everytime he looked at me as if im getting everything he says

  • @Iced-Tea
    @Iced-Tea3 ай бұрын

    Could you not also do $$log_{2}3=(x+1)/(x-5)$$ ? (LaTeX format)

  • @DrFunkman
    @DrFunkman3 ай бұрын

    I figured immediately it was gonna be complicated because (although I could be wrong) there is no integer exponent of 2 that is divisible by 3

  • @Cibakro

    @Cibakro

    3 ай бұрын

    That's right -> Just express any exponent of 2 in terms of primes, you will never have the number 3. The same is true that no exponents of 3 are divisible by 2 for the same reason.

  • @mr_pc-sco197
    @mr_pc-sco197Ай бұрын

    Watching this as a gcse student in the uk knowing this won’t come up in my exams but this was thoroughly interesting

  • @8r.ud_hussein
    @8r.ud_hussein8 күн бұрын

    What does the plate behind you contain? I like to collect things related to mathematics

  • @E_velynn
    @E_velynnАй бұрын

    i somehow went through algebra I and II, precalc, calc I and II, yet never saw any of this and now i feel like i was robbed. this looks so interesting and i am now lamenting never having had a math teacher that makes math interesting. thanks, random math guy on the internet!

  • @Roro-ej7ke

    @Roro-ej7ke

    Ай бұрын

    Same story🤷‍♀️

  • @caseysunderland4927
    @caseysunderland4927Ай бұрын

    As a sophomore in College math, this actually makes sense

  • @ayushkushwaha550
    @ayushkushwaha55023 күн бұрын

    0:45 the quicker method after this step would be to divide x-5 by x+1, which would be equal to ln3/ln2. Now use componendo dividendo on both sides :)

  • @nihinivi9757
    @nihinivi97573 ай бұрын

    What if we do 2^x=3 and then do log on both sides to get x log 2=log 3, log2/log3=x and then 2^x-5=2^(log2/log3)x+1 then do x-5=(log2/log3)x+1 and then work it out?

  • @expiredmilk5435

    @expiredmilk5435

    3 ай бұрын

    X= log3/log2 not log2/log3

  • @prionsarl4929
    @prionsarl49293 ай бұрын

    What would happen if we tried to first integrate or derivate both sides first, and then solve for X?

  • @PrincessHonk
    @PrincessHonk3 ай бұрын

    Nice liked that one

  • @kimsonvu7357
    @kimsonvu73572 ай бұрын

    Thanks u verry much

  • @belaitedwaif2212
    @belaitedwaif2212Ай бұрын

    You can solve this a lot quicker by just splitting up the exponents into 2^x, 2^-5, 3^x, and 3. Then isolating x is a matter of factoring it out of 3^x/2^x. Then you get log(1/(3*2^5)) with a logBASE of 3/2. The answer is -11.26

  • @sparshsharma5270
    @sparshsharma52703 ай бұрын

    I always do the first way and it's simple for me.

  • @MrTheStephReal
    @MrTheStephReal3 ай бұрын

    But if you can use any log fir the first solution, how do I know that the result doesn't change depending on that

  • @somaannn

    @somaannn

    3 ай бұрын

    because you take the same log on both sides of the equation. Like if you do +3 on both sides, it doesnt change anything since it cancels out.

  • @canirunit8162
    @canirunit8162Ай бұрын

    I'm not sure why I'm clicking on this. I am an economics student and just reading about consumer behavior theory, and it contains Lagranian function, which I've never heard before and try to find wtf is that equation but anyway I'm satisfied with this video.

  • @aizxensrq5076
    @aizxensrq50763 ай бұрын

    Am i still correct if i do the "prettier way" but i use ln 2/3 instead of log base 2/3??

  • @aheinrich2535

    @aheinrich2535

    3 ай бұрын

    Yes

  • @saciookta334
    @saciookta3343 ай бұрын

    Does (5.2log9) same?

  • @whydoineedname4932
    @whydoineedname49329 күн бұрын

    Taking log on both sides we get (x-5)log2=(x+1)log3 now value of log 2 and log 3 with base e are 0.69 and 1.09 approx So 0.69x-3.45=1.09x+1.09 0.4x=-4.54 x=-4.54/0.4 which is -11.35 So the ans must be around -11.35!

  • @ridoing9969
    @ridoing99693 ай бұрын

    The professor when ever I start copying the notes. 3:34

  • @stolenmonkey7477

    @stolenmonkey7477

    3 ай бұрын

    That made me laugh a bit lol

  • @waliullahmazumder
    @waliullahmazumder29 күн бұрын

    I just woke up in the afternoon,and a pg student of computer science,, still watching this before eating by breakfast

  • @FlynnFromTaiga
    @FlynnFromTaiga3 ай бұрын

    It's long. You can write it like (2^x)/32=3*3^x from where you can easily go to (2/3)^x=32*3

  • @ocaraqe1cara194
    @ocaraqe1cara1942 ай бұрын

    Idk why the heck im watching this in 3 year of high school but hell yeah this is so freaking cool

  • @LorxusIsAFox
    @LorxusIsAFox3 ай бұрын

    Not an approximation; the two answers are exactly the same. This we can see through a combination of the change of base formula and mainpulation of logs in the numerator and denominator of version #1: ln 3 + 5 ln 2 = ln 3 + ln 32 = ln 96; ln 2 - ln 3 = ln 2/3. As for a workable approximation, we should clean this up a bit first: for X = ln(96)/ln(2/3), we have X = -ln(96)/ln(3/2), and conveniently for log approximations, 3/2^2 ~ sqrt(5), 3/2^3 ~ sqrt(11). Now, 9870/9216 ~ 1.071, so we take 96^2 = 9216 ~ 9870 = 11^3 * sqrt(11) * sqrt(5) ~ (3/2)^23, 96 ~ (3/2)^23/2 for a final approximation of X = -11.5, which seems to agree OK with calculator results of ~-11.257.

  • @CuriousMindDevesh

    @CuriousMindDevesh

    2 ай бұрын

    I exactly do this and get a error of approx. 0.25

  • @archit5031
    @archit5031Ай бұрын

    I m a bio student why am watching this Great explanation 👍

  • @ceegers
    @ceegers3 ай бұрын

    Being a math tutor, at least around where I am, these days everybody's calculator is able to do logs with an arbitrary base, whether directly with the button or further inside a menu.

  • @MCFC-OK-
    @MCFC-OK-3 ай бұрын

    oh my fricking god how many whiteboard pen boxes do you have😂

  • @shrike1861
    @shrike18613 ай бұрын

    When do we use ln and log in both sides?

  • @iancoffey2797

    @iancoffey2797

    3 ай бұрын

    @shrike1861 When the base of the exponents (here they are the 2 and 3) cannot be written as a power of either. e.g. if one side had 2^x and the other side had 32^x-1 we could rewrite the 32 as a power of 2, making it 2^5(x-1). You can then remove the common base and solve. That can't be done here so you must use log or ln

  • @Zhiowe
    @Zhiowe2 ай бұрын

    Learned logarithms 4 months ago, forgot them, then relearned them here

  • @dhruvbhargava2559
    @dhruvbhargava25593 ай бұрын

    is 48 an option ?

  • @guywithcapacitors
    @guywithcapacitors3 ай бұрын

    Can't we simply do it like this? Applying log on both sides We have X-5)log2=x+1)log3 Now taking x+1 to the left side and log2 to right side. X-5/x+3=log3/log2 Applying division rule of log we get log3/log2=log (3-2) That is 0 So X-5/x+3=0 So X=5? Am a rookie at maths,so please tell me its correct or not

  • @ra1yms0up

    @ra1yms0up

    2 ай бұрын

    The log division rule is incorrect, and why x + 3 in the denominator?

  • @guywithcapacitors

    @guywithcapacitors

    2 ай бұрын

    ​@@ra1yms0up how is that incorrect, could you please tell And that x+3 is in the denominator cause it was multiplied in RHS I just got it to the LHS

  • @ra1yms0up

    @ra1yms0up

    2 ай бұрын

    @guywithcapacitors You can't turn log3/log2 to log(3-2), I think you meant log3-log2 = log(3/2) The incorrect rule you used works for exponents, so use them to rewrite an equation (I personally solved it like this): 2^(x-5) = (2^x)/(2^5) 3^(x+1) = (3^x)*3 We'll get: (2^x)/32 = (3^x)*3 Move 32 to the RHS and 3^x to the LHS: (2^x)/(3^x) = 32 * 3 32 * 3 = 96 x is an exponent for both 2 and 3, so you can take it out (2^x/3^x = (2/3)^x): (2/3)^x = 96 And that's it. You x is a log of 96, base 2/3 But I still can't understand where you got x+3 if there's x+1

  • @guywithcapacitors

    @guywithcapacitors

    2 ай бұрын

    @@ra1yms0up ohhh thank you mate I really had messed up in that log part!😅 And yes that is x+1,so sorry from my part for putting that x+3😶‍🌫️

  • @spspspd
    @spspspd3 ай бұрын

    로그공식 까먹었던 걸 복습하게 되는 영상. 이거보고 다시 생각났네요

  • @snmnurr

    @snmnurr

    25 күн бұрын

    Hi in which grade do you learn logarithms in Korea?

  • @spspspd

    @spspspd

    25 күн бұрын

    @snmnurr people learn logarithms in 11th grade in Korea, but Im now in high school in the US :)

  • @garrettbates2639
    @garrettbates26393 ай бұрын

    Equivalent answer with slightly less distribution: 2^(x - 5) = 3^(x + 1) (x - 5) ln 2 = (x + 1) ln 3 x - 5 = (x + 1) log2(3) x - 5 = x log2(3) + log2(3) x - x log2(3) = 5 + log2(3) x = (5 + log2(3)) / (1 - log2(3))

  • @vibhashsingh7547
    @vibhashsingh7547Ай бұрын

    2:25 imo you should have transposed the terms to other side respectively instead of subracting/adding on both the sides

  • @amitapatil1881

    @amitapatil1881

    Ай бұрын

    Anime Dekhne Vale life mae kuch nahi kar sakte

  • @davidthomasxyz
    @davidthomasxyz3 ай бұрын

    very nice.

  • @makakh2620
    @makakh26202 ай бұрын

    Bro he the goat

  • @adithyakashyap5845
    @adithyakashyap58453 ай бұрын

    Why not take log on both sides and apply Log(x)^n = nlogx And then reduce it to (x-5)log2=(x+1)log3

  • @unholyravioli989

    @unholyravioli989

    3 ай бұрын

    That's precisely what he did

  • @adithyakashyap5845

    @adithyakashyap5845

    3 ай бұрын

    Oh😂...

  • @pappujha8577
    @pappujha857725 күн бұрын

    Why did you not use log table

  • @jivitesh5114
    @jivitesh51143 ай бұрын

    Why not just get a log table and put values of log2 and log3

  • @violate6332

    @violate6332

    2 ай бұрын

    It could come up on an exam where you cant use calculators or the log table

  • @Yonkage-ik5qb
    @Yonkage-ik5qbАй бұрын

    Took precalculus in high school roughly 20 years ago. NEVER learned this.

  • @travo6805
    @travo68052 ай бұрын

    I played Mario kart tour every day during honors precalc in high school and I regret it every day as an engineering major in university

  • @reeceherman555
    @reeceherman555Ай бұрын

    I'm a sophomore engineer major at a top university in the nation and had zero clue how to do this. I'm cooked

  • @user-dl2mu3br5r
    @user-dl2mu3br5r3 ай бұрын

    Can you solve this equation please? e^(x-1)/x =x I know that x equals 1, but I did not know how to prove it

  • @Inventron19
    @Inventron193 ай бұрын

    What I like the best about this guy is he still uses a whiteboard and not a smart board

  • @camperkiller3
    @camperkiller32 ай бұрын

    I don't know if anyone else has pointed this out, but you shouldn't have used x at the end when explaining how to use the change of base rule. It will definitely confuse people who are not very familiar with math as you have an equation for x right next to it on the board.

  • @TheRealFallenDemon
    @TheRealFallenDemon3 ай бұрын

    Damn, if you were my high school teacher I would have learned mathematical induction way before the week before my final exam

  • @vivicries
    @vivicries20 күн бұрын

    i just approximated to solve it quickly: x-5/x+1 = log3/log2 x-5/x+1 = 0.4771/0.3010 10x-50 = 16x+16 x=-11

  • @markosverdhi
    @markosverdhi3 ай бұрын

    My friends in my old algebra class had a funny way of remembering the ln(x^2)=2lnx theorem. We called it the yeet theorem because you take the exponent and yeet that shit to the front

  • @ritikkumargg304
    @ritikkumargg3042 ай бұрын

    You are great

  • @primeyt422
    @primeyt4222 ай бұрын

    It's crazy how i first saw the question in the thumbnail and knew that i had to add log on both sides

  • @Angelahuofficial
    @Angelahuofficial2 ай бұрын

    I got -11.256, but my calculations is a bit off bc i did it my way so wasnt sure how to get the exact number

  • @toaster4693
    @toaster46932 ай бұрын

    Why not just take log base 2 of both sides in the beginning? It's more sensible than either option.

  • @SuperDeadparrot
    @SuperDeadparrot22 күн бұрын

    x = ln(96)/ln(2/3) + 2*pi*i/ln(2/3) * k where k is an integer. When k=0, you get a real answer.

  • @mgrb3
    @mgrb32 ай бұрын

    My reaction if this was a question on the test: Answer test C Seems right

  • @Rocket_browser
    @Rocket_browser2 ай бұрын

    indians and asians are the only two people i trust to teach me maths. Indians for basics to intermediate and for advance i trust asians

  • @zelbayanym
    @zelbayanymАй бұрын

    that's way more complicated way that i was taught in school lmao

  • @GhostWithAHoodie
    @GhostWithAHoodie2 ай бұрын

    I'm not good at it, but I just love calculus and math now that I'm in college