Question

(x+2) (x+3)+(x+3) 2 elevado ao cubo

Answer 1

(x+2) . (x+3) + (x+3) . 2³ = 0
x² + 3x + 2x + 6 + (x + 3) . 8 = 0
x² + 5x + 6 + 8x + 24 = 0
x² + 5x+ 8x + 24 + 6 = 0 
x² + 13x + 30 = 0   

Se quiser apenas o produto notável : x² + 13x + 30 = 0   

Se quiser a raiz da equação:

a = 1 
b = 13
c = 30

Δ = b² -4 .a . c
Δ = 13² -4 . 1 . 30
Δ = 169  - 120
Δ = 49

$\mathtt{\dfrac{-b+-~\sqrt{\Delta}}{2~.~a}~~=~~\dfrac{-13+-~\sqrt{49}}{2~.~1}~~=~~\dfrac{-13+-~7}{2}} \\ \\ \\ \mathtt{x' = \dfrac{-13+7}{2}~~=~~-\dfrac{6}{2}~~=~~-3} \\ \\ \\ \mathtt{x'' =\dfrac{-13-7}{2}~~=~~-\dfrac{20}{2}~~=~~-10} \\ \\ \\ \mathtt{S = -10~~~e~~~-3}$