Euler’s Totient Function (Solved Examples)

Network Security: Euler’s Totient Function (Solved Examples)
Topics discussed:
1) Definition of Euler’s Totient Function Ф(n) or Phi Function Phi(n).
2) Explanation on how to find the Ф(n).
3) Solved examples of finding Ф(n) for larger numbers using formulas.
4) Various scenarios of n in Ф(n) such as ‘n’ being prime, ‘n’ being a product of two prime, and ‘n’ is a product of composite-prime-composite combination.
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Пікірлер: 99

  • @harshitshukla1974
    @harshitshukla19745 ай бұрын

    The last formula where phi(n) = n * ( 1 - 1/p) * ( 1 - 1/q) * ( 1 -1/r) .... where p,q,r.... are the distinct prime factors of n is applicable to all the cases. So it can be treated as the one and only required formula. PS: thanks for the great content.

  • @AkshayKumar-re6kl
    @AkshayKumar-re6kl2 жыл бұрын

    369=>41*3*3; phi(369)=>369*(1-1/41)(1-1/3)=240 372=>31*3*2*2; phi(372)=>372*(1-1/31)(1-1/3)(1-1/2)=120

  • @hossammahmoud6821

    @hossammahmoud6821

    Жыл бұрын

    how did u know that u must use 3 and 41 for Φ(369)? how did u know that u must use 2, 3 and 31 for Φ(372)? how did u reach there?

  • @cs1-34devabalamb9

    @cs1-34devabalamb9

    Жыл бұрын

    @@hossammahmoud6821 he did prime factorization on 369 and 372

  • @amanmotghare7196

    @amanmotghare7196

    4 ай бұрын

    thanks

  • @rajeshprajapati4863
    @rajeshprajapati48632 жыл бұрын

    Answer to H.W : 1 : Φ(369) = 240 2 : Φ(372) = 120 So, there are 240 and 120 positive integers that are less than 369 and 372 respectively, also relatively prime to 369 and 372 respectively.

  • @editorsam8813

    @editorsam8813

    Жыл бұрын

    Write bro

  • @omop5922

    @omop5922

    Жыл бұрын

    @@editorsam8813 right hota hai

  • @amaviamah2274
    @amaviamah227410 ай бұрын

    You are one of the best teachers so far. Thanks for this amazing video that explains everything the simplest way.👏👏

  • @balajimetla3886
    @balajimetla3886 Жыл бұрын

    very nice explanation sir. continue like this

  • @swarnalatha7892
    @swarnalatha7892 Жыл бұрын

    Excellent lecture

  • @quratulain4314
    @quratulain4314 Жыл бұрын

    Excellent lecture Thanks alot

  • @thanmaijami8962
    @thanmaijami89622 жыл бұрын

    Answers: 240,120

  • @Arihantdesai413

    @Arihantdesai413

    7 ай бұрын

    Sure

  • @maryliezlgorzal1365
    @maryliezlgorzal13652 ай бұрын

    Thank you so much sir.

  • @poonamkumari8525
    @poonamkumari85252 жыл бұрын

    Sir, It's my humble request 🙏🏻 Plz add more video in playlist of data structure. Plz plz🙏🏻🙏🏻🙏🏻🙏🏻

  • @sastenashe_yt8802
    @sastenashe_yt88022 жыл бұрын

    Great video

  • @saritasethi6202
    @saritasethi6202 Жыл бұрын

    Thank you so much😊

  • @thedevourerofgods1686
    @thedevourerofgods16862 жыл бұрын

    yo thanks for teaching me this

  • @hellostranger2709
    @hellostranger2709 Жыл бұрын

    My finals will be in a a few hours. Thank you for the clear explanation! :D

  • @Mahi-nz5ct

    @Mahi-nz5ct

    Жыл бұрын

    Which event were you participating?

  • @parmarh3898

    @parmarh3898

    Жыл бұрын

    Pass or failed?

  • @theblueworld1188
    @theblueworld1188 Жыл бұрын

    Thanks sir👍👍

  • @manikandan-m.
    @manikandan-m. Жыл бұрын

    = phi(3 * 123) = phi (3² * 41¹) ; = 369 * (1 - 1/3) * (1 - 1/41) ; = 369 * 2/3 * 40/41; = 3 * 80 = 240; Thus, 240 numbers are the positive integers that are relatively prime which is less than the given, 369; = Phi(3 * 124) = phi(3 * 31 * 2²) ; = 372 * (1 - 1/3) (1 - 1/31) (1 - 1/2) ; = 372 * 2/3 * 30/31 * 1/2; = 12/6 * 60 = 120; Therefore, 120 positive numbers are relatively prime and lesser than the given, 372.

  • @roystargamingfreefire7987
    @roystargamingfreefire7987 Жыл бұрын

    Thanks bro i learn it,👍..by the way ur answers 240 and 120.

  • @Valsula69
    @Valsula693 ай бұрын

    Best explanation I’ve found for this. Thanks!

  • @walidmenghour2639
    @walidmenghour26392 жыл бұрын

    phi(369) = 2^2*41=240 phi(372)=2^2*3*31=120 thank you for this video ;)

  • @neelamyadav7609

    @neelamyadav7609

    2 жыл бұрын

    I think there is 3^2*41 =240.

  • @mandelaaa
    @mandelaaaАй бұрын

    I love you so much sir

  • @shloksuman8164
    @shloksuman8164 Жыл бұрын

    LIFE SAVER!!!

  • @trendystatusforyou
    @trendystatusforyou9 ай бұрын

    What if the prime numbers p and q are same? How do we calculate?

  • @karaganilokeswari2301
    @karaganilokeswari2301 Жыл бұрын

    Sir pi of thousend lo 2,5 prime number so formula wrong sir second formula may substitute

  • @hossammahmoud6821
    @hossammahmoud6821 Жыл бұрын

    for the solution of the homwork how did u know that u must use 3 and 41 for Φ(369)? how did u know that u must use 2, 3 and 31 for Φ(372)? how did u reach there?

  • @rnboy0

    @rnboy0

    10 ай бұрын

    You learn how to factorize a number from youtube then come

  • @ashutosh1727

    @ashutosh1727

    6 ай бұрын

    you need to study 7th class mathematics again

  • @aissalaribi7672
    @aissalaribi76723 ай бұрын

    Great movie, however it would have been good to solve bigger number such as phi(33389)

  • @priyavats1847
    @priyavats1847 Жыл бұрын

    The answer is (i) 240 ,there are 240 number less than 369 that are relatively prime to 369. (ii) 120 , there are 120 numbers less than 372 that are relatively prime to 372.

  • @amanrawat3248
    @amanrawat32482 жыл бұрын

    Thank you thank you thank soo much sir. .i want to touch your feet .. seriously i wasted 2 hour in internet for just learning this thing 😂😂😂

  • @NCS8331
    @NCS8331Ай бұрын

    How to find for 761

  • @rehansekh2164
    @rehansekh21642 жыл бұрын

    Answer of homework questions 1. Phi(369)=240 2. Phi(372)=120

  • @IT.Diwakar
    @IT.Diwakar2 жыл бұрын

    Solve for phi(25) is it same as n is prime! i.e. phi (25)= n-1=25-1=24?

  • @RichaSingh-sy7hz

    @RichaSingh-sy7hz

    2 жыл бұрын

    But 25 is not a prime number. I think as it is 5^2, so we we take n=5. phi(5)=n-1, n=4.

  • @l032radhakulkarni7
    @l032radhakulkarni79 ай бұрын

    Phi of 369 is 240 and phi of 372 is 120❤️

  • @GreatestIndianRailways
    @GreatestIndianRailways Жыл бұрын

    Ans:-Q1-240,Q2-120

  • @MMNayem-dq4kd
    @MMNayem-dq4kd2 жыл бұрын

    phi(369)=240 phi(372)=120

  • @sathvicendra4108
    @sathvicendra41082 жыл бұрын

    How to solve phi(25) Can any body help

  • @Mathchemist__
    @Mathchemist__2 жыл бұрын

    Can anyone share the full solution of the homework? I wanna see it

  • @PRITESHKRSRV

    @PRITESHKRSRV

    Жыл бұрын

    369 = 3^2 X 41 Distinct primes = 3,41 phi(368) = 369 X (1-1/3) X (1-1/41) = 369 X 2/3 X 40/41 = 240 Same Approach for phi(372)

  • @pruthvirajgspruthvi4315

    @pruthvirajgspruthvi4315

    Жыл бұрын

    @@PRITESHKRSRV but another 3 is not calculated y please explain me..👀

  • @adityarai30

    @adityarai30

    Жыл бұрын

    @@pruthvirajgspruthvi4315 use distinct prime formula discussed in video

  • @pulamarasettinaveen2878
    @pulamarasettinaveen28782 жыл бұрын

    if i solve phi(1000) according to second formula i was getting 4. note(here 2 and 5 both are prime numbers )

  • @PRITESHKRSRV

    @PRITESHKRSRV

    Жыл бұрын

    Kid read the second formula again. product of 2 and 5 is not equal to 1000

  • @photon_gaming1765
    @photon_gaming176510 ай бұрын

    ∅(369) =240 ∅(372) =120 😊 thank you creators, always helping me to revise quickly before exams.. ❤

  • @The.Jaynish
    @The.Jaynish2 жыл бұрын

    How can we cross check whether ans is correct or not?

  • @PRITESHKRSRV

    @PRITESHKRSRV

    Жыл бұрын

    Apply Standard method, calculate GCD of each digit and verify. That's all you can

  • @ujjwalgautam7341
    @ujjwalgautam7341 Жыл бұрын

    Answers are 240 and 120

  • @rashiagrawal7934
    @rashiagrawal7934Ай бұрын

    1. 240 2. 120

  • @vrajpatel8302
    @vrajpatel83022 жыл бұрын

    240&120

  • @sadinenisushanth887
    @sadinenisushanth887 Жыл бұрын

    how to find phi of 25

  • @shrutibiswas1530

    @shrutibiswas1530

    8 ай бұрын

    Using the 3rd formula. 25×(1-1/5)=20

  • @donthusravya2026
    @donthusravya20262 жыл бұрын

    phi(369)=240 , phi(372)=120

  • @sandrabm3224

    @sandrabm3224

    2 жыл бұрын

    how u got the 1st answer

  • @janakiisajeev
    @janakiisajeev2 жыл бұрын

    ❤️

  • @bhagavantulasi5150
    @bhagavantulasi5150 Жыл бұрын

    Can anyone say of n=49, answer

  • @mehedihassanshimul2248

    @mehedihassanshimul2248

    3 ай бұрын

    42

  • @davidwebdeveloper
    @davidwebdeveloper Жыл бұрын

    369 = 123 * 3 = 122 * 2 = 244

  • @hardikkumarsingh

    @hardikkumarsingh

    5 ай бұрын

    123 is not a prime no. , so this is wrong

  • @shrutikadambhare7650
    @shrutikadambhare7650 Жыл бұрын

    How you people got to know the factors of 369 and 372?

  • @subratamandal2924

    @subratamandal2924

    4 ай бұрын

    In this cases you have to calculate factors, by dividing starting from 2 and onwards

  • @SARPONGBLESSINGABENA
    @SARPONGBLESSINGABENA2 ай бұрын

    240 and 120

  • @annonymous.
    @annonymous.2 жыл бұрын

    11:13 phi(1000) = 40

  • @renositon4344

    @renositon4344

    2 жыл бұрын

    400 po

  • @katrinamaeponcio3386
    @katrinamaeponcio338611 ай бұрын

    224; and 330

  • @user-pb6nz5of4t
    @user-pb6nz5of4t Жыл бұрын

    240,120

  • @iqraibrar7216
    @iqraibrar7216 Жыл бұрын

    Phi(27)

  • @mehedihassanshimul2248

    @mehedihassanshimul2248

    3 ай бұрын

    18

  • @aryangoel4893
    @aryangoel4893 Жыл бұрын

    240 n 120

  • @nitishjha7756
    @nitishjha77565 ай бұрын

    Sir but how would we solve for 25😢😢😢

  • @Varsha_Thomas

    @Varsha_Thomas

    4 ай бұрын

    Use the third formula. n*(1-1/p) = 25*(1-1/5) = 25*⅘ = 20 The second formula is not possible. We know that 25 = 5*5, however here p and q are NOT distinct. They should be distinct in order to use the second formula.

  • @Varsha_Thomas

    @Varsha_Thomas

    3 ай бұрын

    ​@user-kf1yq8nv8x but isn't the answer 20?👀

  • @Varsha_Thomas

    @Varsha_Thomas

    3 ай бұрын

    @user-kf1yq8nv8x But isn't the answer 20?

  • @onyiesther178
    @onyiesther1786 ай бұрын

    1:13

  • @devpriyashivani1855
    @devpriyashivani1855 Жыл бұрын

    1. Φ(369) = 240 Prime Factors of 369 = [3 * 3 * 41] = [3^2 *41] Φ(369) = 3 * 3 * 41 * (1-1/3) * (1-1/41) = 3 * 3 * 41 * 2/3 * 40/41 = 3 * 2 * 40 = 240 2. Φ(372) = 120 Prime Factors of 372 = [2 * 2 * 3 * 31] = [2^2 * 3 * 31] Φ(372) = 2 * 2 * 3 * 31 * (1-1/2) * (1-1/3) * (1-1/31) = 2 * 2 * 3 * 31 * 1/2 * 2/3 * 30/31 = 2 * 1 * 2 * 30 = 120

  • @hossammahmoud6821

    @hossammahmoud6821

    Жыл бұрын

    how did u know that u must use 3 and 41 for Φ(369)? how did u know that u must use 2, 3 and 31 for Φ(372)? how did u reach there?

  • @sohagdhali827
    @sohagdhali8272 жыл бұрын

    Phi(25)=20

  • @sathvicendra4108

    @sathvicendra4108

    2 жыл бұрын

    How by using eulers

  • @sohagdhali827

    @sohagdhali827

    2 жыл бұрын

    @@sathvicendra4108 5^2=25 that's why 25*(4/5)=20

  • @tsunningwah3471
    @tsunningwah34715 ай бұрын

    bi

  • @user-pu2tg5xu1c
    @user-pu2tg5xu1c8 ай бұрын

    What about the last formula ?? n=a×b.... Composite...where is s or b in the formula?// COMPLETELY WRONG FORMULA FOR THE LAST ONE!!

  • @karthickkarthick1049
    @karthickkarthick10492 жыл бұрын

    Pi(369)=60 pi (372)=60

  • @monicabattacharya6416
    @monicabattacharya64162 жыл бұрын

    Please start teaching FULL STACK DEVELOPMENT COURSE. I am learning now 😌. if you start it now , it will be helpful for many students who are preparing for placements.

  • @Umar-nl3ny

    @Umar-nl3ny

    2 жыл бұрын

    you are everywhere asking for something, pls take it easy on him and yourself

  • @tejavarma7900
    @tejavarma790011 ай бұрын

    phi(369) = 240 phi(372) = 120

  • @mdafeef3911
    @mdafeef39112 жыл бұрын

    phi(369) = 240, phi(372) = 120

  • @akarshmalhotra1154
    @akarshmalhotra11542 жыл бұрын

    phi ( 369 ) = 240 phi ( 372 ) = 120

  • @sandrabm3224

    @sandrabm3224

    2 жыл бұрын

    how u got the 1st answer

  • @akarshmalhotra1154

    @akarshmalhotra1154

    2 жыл бұрын

    @@sandrabm3224 factors of 369 are 3,41 . One of the factors are composite which means Case 3 is applicable i.e 369 * (1-1/3) * (1-1/41) = 240

  • @navinsingh2784

    @navinsingh2784

    2 жыл бұрын

    @@akarshmalhotra1154 But 3 and 41 both are prime so how it can fall under Case 3??

  • @ritidipsarkar618
    @ritidipsarkar618 Жыл бұрын

    phi(369) = 240 phi(372) = 120