Question

4- Dado o polinômio:
P(x) = x3 + 2x²
– X – 1
Qual o valor de P(2) – 2P(-1)?
A) -10
B) 11
C) 12
D) 8

Answer 1

Resposta:

$p(x) = {x}^{3} + 2 {x}^{2} - x - 1 \\\\ p(2) = {3}^{3} + 2( {2}^{2} ) - 2 - 1 \\\\ p(2) = 9 + 2(4) - 3 \\ \\ p(2) = 9 + 8 - 3 \\\\ p(2) = 14\\ \\ p( - 1) = {( - 1)}^{ 3} + 2( {( - 1)}^{2} ) - ( - 1) - 1 \\\\ p( - 1) = - 1 + 2( 1) + 1 - 1 \\ \\ p( - 1) = - 1 + 2 + 0\\\\ p( - 1) = 1$

$p(2) - 2p( - 1) = \\\\ 14 - 2(1) = \\\\ 14 - 2 \\ \\ p(2) - 2p( - 1) = 12$

Opção 12

Bons Estudos!