Logarithms Part 1: Evaluation of Logs and Graphing Logarithmic Functions
What are logs? No not like the ones from trees, silly! We need to know about logarithms. They represent the inverse operation of exponentiation. How do they work? How do we evaluate them? How do we graph them? Let's go through the basics now.
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Пікірлер: 69
Whoops! At 0:50, I meant to show an exponential equation, like 2^x, instead of x^2, as 2^x is the proper inverse of log base 2 of x. Sorry!
@ramayanishukla4365
4 жыл бұрын
Happens
@angelisvegan5826
3 жыл бұрын
@Dhruv Chaturvedi exactly.. I'm confused.. totally confused
@angelisvegan5826
3 жыл бұрын
Help me professor.. I ain't getting that 2:51 point.. log base b of (y) = x should be the inverse function of y=b^x.. And look what you've written
@randypreston9377
2 жыл бұрын
you all prolly dont care but does any of you know a tool to log back into an Instagram account? I somehow forgot my login password. I love any assistance you can give me
@samirmanuel8944
2 жыл бұрын
@Randy Preston instablaster =)
This is the point where mathematicians got tired of creating signs for their operations and just gave up
@youtubeuserdan4017
Жыл бұрын
Imagine if addition looked like add(5,3)=8
@fusion_42
Жыл бұрын
@@youtubeuserdan4017👏
@ivoryas1696
10 ай бұрын
enzoqueijao Eh, _close._
You need to edit the video at 0:50, such that 2^x is the inverse of log_2(x) instead of x^2. However, this was an excellent explanation
@ProfessorDaveExplains
5 жыл бұрын
I can't edit videos once they're posted. I didn't specifically state that the functions are inverses, but I do see how what is shown is misleading. I pinned a comment so hopefully people will catch that!
you are a genius, feynman level explaination, this concept finally clicked for me
Love your videos! Keep it up!
I am here, just revising my studies of logarithm. I hope you will make a playlist of logarithms.
Thank you for including graphing in your videos! The concept that all graphs can be seen as transformations of their most basic form is very important to me, it gives me a very good intuition on the equations and how they relate to their graphs. I have a question, at 2:57 that part always confuses me, why is it that b and x must always be positive? is -3^3 = -27 non-existent in the world of logs??
@ProfessorDaveExplains
6 жыл бұрын
It's a good question! It's simply that only for the set of positive bases can a function be continuous, so we just focus on what is mathematically useful.
@AriaHarmony
6 жыл бұрын
Oh I see! I didn't notice that something like -3^x wouldn't be continuous.. Thanks!
Thank you so much, i was struggling with this, but this video made it work
I love this thank you so much
For anyone who's confused about 2:51 (That he should've wrote log base b of (y) =x), he explained it in 2:21 (How the inverse was derived)
Kya baat hai sir!!! Bohot badhiyaa
bro you are a legend i wish i knhow this channel before All Love For You
Taking precalc rn. You're a life saver.
Good video!
Can you please make a video on Fluid Mechanics? 😭
I have a question, How do you solve (-2)^x=-8, I know the answer is 3 and know the workaround, but cannot solve it only using logarithm's definition.
Thanks king
Even dave the professor makes mistakes. He taught me more than math today.
Is this video made by yourself? Awesome
Great video and work, as always Prof. Dave!! Quick question for you. At the 0:51 mark, isn't the left side supposed to be 2 to the x, instead of x squared, log base 2 would correspond to 2 raised to so.e exponent?
@ProfessorDaveExplains
6 жыл бұрын
ah, technically yes! i guess it's ok because i was just speaking generally and i do the actual derivation properly later, but thanks for catching that!
@angelisvegan5826
3 жыл бұрын
Hey nishant!! A quick question for you too .. How on earth could x rest next to log base 2.. even when x is the exponent.. Cuz exponents aren't supposed to sit next to log base 2...that's the place for "result".... or am I missing something.. Like .. Log base 2 of 8 = 3.. And 8 is but result of 2^3.. but what they're doing is placing exponent in place of the "result"..
Great 👍👍😃
How can log be root over
Prof Dave's tutorial is as clear as a crystal. It is as if David is showing me how to overcome Goliath who is confronting me disguised as Math. Even anencephalous Maxine Waters will be able to understand the Prof.
@enzoqueijao
4 жыл бұрын
Thanks for sharing
Done.
Is 2:52 right? Should y=b^x be logb(y)= x
@insane7493
3 жыл бұрын
yes it is f(x)=b^x then f of inverse of x is log base b of x he is just using y instead of function notation
And what's the difference between root and log? Just expressing differently?
@ProfessorDaveExplains
6 жыл бұрын
totally different operations!
For log x to the base 4 = 1/2, why isn't x = +-2?
@ridmicmeena4123
Жыл бұрын
Same doubt
@abhaypawar7433
9 ай бұрын
negative numbers arent continuous
hi dave i am confused about something you mentioned in 2:58, why couldnt the base be a negative number ? is anything wrong with log -3 (- 1/27)= -3 ? because -3 ^ -3 is - 1/27, isnt it ? or am i missing something ?
@saveearth7907
3 жыл бұрын
And as you know, unless we're getting into imaginary numbers, we can't deal with a negative number underneath a square root. ... So in summary, because we only allow the log's base to be a positive number not equal to 1, that means the argument of the logarithm can only be a positive number.
@felixzeng997
3 жыл бұрын
@@saveearth7907 many thanks
@saveearth7907
3 жыл бұрын
@@felixzeng997 no..thank you..
@truesanatani2892
3 жыл бұрын
@@saveearth7907 you know what.. there could be a problem like yours ..but the makers of logarithm did not allow log base or the argument to be negative..
@techhelper99
Жыл бұрын
@@truesanatani2892 @save earth are you both Twins♊!!
Yaaay i finished the comprehension in like 10 seconds
Mistake correction : square root of x squared is the absolute value of x. Time marker : 0:41
How's that .. 2^x = log2x.. I mean... x wasn't supposed to be there.. Look at this.. 2^3= 8.. and we write it as log base 2 of 8 = 3.. I ain't getting it.. The problem is log base 2 of x.. x is the problem.. x should be outside the equal sign.....
@techhelper99
Жыл бұрын
Log2^x is not equal to 2^x....you are getting it wrong from here itself...
Oh I thought logarithms, exponents and roots were like a three way inverse operations
2:22 can anyone explain please
@slowfern
Жыл бұрын
nvm got it
Always update me
4:00 why not -3?
@primeprime1047
4 жыл бұрын
You're right! We can say x=+/-3 too
@jurilynperez111
3 жыл бұрын
b must be positive and not equal to 1
Once again thank you Jesus of sciences. 🎉
I watched it but I didn’t take notes.