12^13–12^12+12^11
= 12^11(12^2 - 12 + 1)
= 12^11 (133)
but 133 = 7*19
since 133 is divisible by both 7 and 19, the original expression is also divisible by 7 and 19
Prove that:
12^13–12^12+12^11 is divisible by 7 and 19.
3 answers
I dont understand
The answer is 12^11