Question

*Ex. 5 de la Testul 2*

Answer 1

2^n*2*3^n+5*6^n=
=6^n*2+6*n*5 dam factor comun
6^n*7 => e divizibil cu 7

Answer 2

$2 {}^{n + 1} \times 3 {}^{n} + 5 \times 6 {}^{n} = \\ = (2 \times 3) {}^{n} \times2 {}^{1} + 5 \times 6 {}^{n} = \\ = 6 {}^{n} \times 2 + 5 \times 6 {}^{n} = \\ = 6 {}^{n} (2 + 5) = \\ = 6 {}^{n} \times 7$
divizibil cu 7

Sper ca te-am ajutat!