Question

Sejam os polinômios A(x) = x3 – x2 + x – 1 e B(x) = -3x2 + x + 2 , calcule:
a) A (1/2) ‒ B(‒1) b) A(0) + B(1)

Answer 1

A(x) = x³ – x² + x – 1
B(x) = -3x² + x + 2


A(x) = x³ – x² + x – 1
A(1/2) = (1/2)³ - (1/2)² + (1/2) - 1
A(1/2) = 1/8 - 1/4 + 1/2 - 1
A(1/2) = (1 - 2 + 4 - 8)/8 = -5/8

A(0) = 0³ - 0² + 0 - 1 = 1

B(x) = -3x² + x + 2
B(-1) = -3(-1)² + (-1) + 2 = -3(+1) -1 +2 = -3 -1 + 2 = -2
 
B(x) = -3x² + x + 2
B(1) = -3(1)² + (+1) + 2 = -3(+1) +1 +2 = -3 -+1 + 2 = 0


a) A (1/2) ‒ B(‒1) 
-5/8 -( -2 ) = -5/8 + 2 = (-5 + 16)/8 = 11/8

b) A(0) + B(1)
1 +0 = 1