Waste less time on Facebook — follow Brilliant.
×

Euler's Theorem

Euler's theorem relate to the remainder of various powers and has applications ranging from modern cryptography to recreational problem-solving. See more

Level 2

         

What is the last digit of \( 2^9\)?

For a positive integer \(n>2,\) what can we say about the number of positive integers less than \(n\) that are relatively prime to \(n\) (that is, their GCD is 1)?

Hint: A useful property of the Greatest Common Divisor function is \(\gcd(a,b) = \gcd(a,a-b);\) e.g., \(\gcd(10,8) = \gcd(10,2) = 2.\)

Find the last two digits of \(7^{100}-3^{100}.\)

What is the largest integer that always divides \(n^{7}-n\) for any integer \(n?\)

\[\LARGE \color{blue}5^{\color{green}5^{\color{red}5^{\color{brown}5^\color{magenta}5}}}\]

What are the last three digits of the number above?

×

Problem Loading...

Note Loading...

Set Loading...