Question

Am nevoie urgent! Ma va asculta❤️dau coroana dar va rog

Answer 1

$\it = [7^5-(7+1)\cdot7^4+(7+1)\cdot7^3-(7+1)\cdot7^2+(7+1)\cdot7-7-1]^n=\\ \\ =(7^5-7^5-7^4+7^4+7^3-7^3-7^2+7^2+7-7-1)^n=(-1)^n=\\ \\ \\ =\begin{cases} \it -1;\ pentru\ n-impar\\ \\ \it 1;\ pentru\ n-par\end{cases}$