Question

Efetue corretamente as multiplicações dos polinômios:
a) (4x) . (x² + 5x -1)

b)(3a+b) . (3a-b)

c) (x+1) . (x² + 7x -10)

d)(5x³ + x² -4x) . (2x² -3x +5)

Answer 1

A) (4x) . (x²+5x-1) = 4x.x² + 4x.5x + 4x.(-1) = 4x³ + 20x² - 4x

B) (3a+b) . (3a-b) = 3a.3a + 3a.(-b) + b.3a + b.(-b) = 9a² - b²

C) (x+1) . (x² + 7x -10) = x.x² + x.7x + x.(-10) + 1.x² + 1.7x + 1.(-10) = x³+8x²-3x-10

D) (5x³ + x² -4x) . (2x² -3x +5)=

5x³ . (2x² -3x +5) + x². (2x² -3x +5) - 4x . (2x² -3x +5)=

10x⁵ - 15x⁴ + 25x³ + 2x⁴ - 3x³ + 5x² - 8x³ + 12x² - 20x =

10x⁵ - 13x⁴ + 14x³ + 17x² - 20x