i just can't finish up these proofs but i have my ideas written down on the bottom. also, i have what i think is right written down, but it IS A LOT of stuff to type. can anyone point me in the correct direction to go?(adsbygoogle = window.adsbygoogle || []).push({});

i need to show that if gcd(a,n)=(a-1,n)=1, then 1+a+...+a^0 mod n

show (m,n)=1 then m 1 mod (mn)

show if m and k are positive integers then (^k)=m^k-1(m)

what i know so far: the second one can use fermat's little theroem correct? if a==0 mod b and b==0 mod a then => ab==0 mod(ab)

the third one is just playing with my brain, i honestly do not know anywhere to start it.

the first question says what a,n are relatively prime, and a-1,n are also relatively prime. so, if any a raised to a power, that a is == to 0, mod n. can anyone give me a "hint"?

thank you!! p.s. does my LaTeX look good? feel free to tell me and all.

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# Please help, almost finished

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