I'm trying to prove that $\displaystyle 7|(3^{2n+1}+2^{n+2})$
Anyway, I've simplified the RHS to $\displaystyle 3*9^n+4*9^n$
How can I "pull out" $\displaystyle (3+4)$ here? ie, make it so that
$\displaystyle 3*9^n+4*9^n=(3+4)*(???)$
Thanks!
I'm trying to prove that $\displaystyle 7|(3^{2n+1}+2^{n+2})$
Anyway, I've simplified the RHS to $\displaystyle 3*9^n+4*9^n$
How can I "pull out" $\displaystyle (3+4)$ here? ie, make it so that
$\displaystyle 3*9^n+4*9^n=(3+4)*(???)$
Thanks!