Question

Vă rog DAU COROANA!!! ​Ambele exerciții

Answer 1

Răspuns:

1.

${9}^{n + 1} = {3}^{2(n + 1)} = {3}^{2n + 2}$

${3}^{2n + 2} - {3}^{2n} \times 5 = {3}^{2n} ( {3}^{2} - 5)$

$= {3}^{2n} \times 4 = {3}^{2n} \times {2}^{2} = {( {3}^{n} \times 2) }^{2}$

Care este pătrat perfect

2.

${4}^{x} = {2}^{2x}$

${8}^{x + 1} = {2}^{3x + 3}$

${4}^{x} \times {2}^{x + 2} = {2}^{2x} \times {2}^{x + 2} = {2}^{3x + 2}$

${2}^{3x} + {2}^{3x + 2} + {2}^{3x + 3} = 832$

${2}^{3x} (1 + {2}^{2} + {2}^{3} ) = 832$

${2}^{3x} \times 13 = 832$

${2}^{3x} = 64$

${2}^{6} = 64$

$3x = 6$

$x = 2$