Question

va rog frumos sa ma ajutati cine răspunde fara sens report ​

Answer 1

Explicație pas cu pas:

29.

$x = {2}^{n} + {2}^{n + 1} + {2}^{n + 2} + {2}^{n + 3} = {2}^{n} \cdot (1 + 2 + {2}^{2} + {2}^{3})$

$= {2}^{n} \cdot (1 + 2 + 4 + 8) = {2}^{n} \cdot 15 \bf \ \ \vdots \ \ 15$

$\implies x \bf \ \ \vdots \ \ 15$

30.

$x = {3}^{n + 3} - {3}^{n + 2} - {3}^{n + 1} - {3}^{n} = {3}^{n} \cdot (3^{3} - {3}^{2} - 3 - 1) =$

$= {3}^{n} \cdot (27 - 9 - 3 - 1) = {3}^{n} \cdot 14 \bf \ \ \vdots \ \ 14$

$\implies x \bf \ \ \vdots \ \ 14$