Question

1) A expressão (x + 3) ³ é igual a : *

A) x³ + 6 x² + 9x + 27

B) x³ + 9x² + 27x + 27

C) x³ + 9x² + 9x + 27

D) x³ + 6x² + 27x + 27

Answer 1

Resposta:

alternativa b) x³ + 9x² + 27x + 27

Answer 2

$\sf (x + 3) ^{3}$

$\sf (x + 3)\cdot (x + 3)\cdot (x + 3)$

$\sf (x + 3)\cdot ( {x}^{2} + 3x + 3x + 9)$

$\sf (x + 3)\cdot ( {x}^{2} + 6x+ 9)$

$\sf {x}^{3} + 6 {x}^{2} + 9x + 3 {x}^{2} + 18x + 27$

$\sf {x}^{3} + 6 {x}^{2} + {3x}^{2} + 9x + 18x + 27$

$\red{\sf {x}^{3} + 9 {x}^{2} + 27x + 27}$

$\boxed{\boxed{\sf Letra \: B}}$