Question

3° Calcule as multiplicações.

a) (4-x)×(3x²-2x+8)

b) (2y-x)×(4+x²)

c) (3a+b⁴)×(-4a-5b)

d) (4x³+3x+1)×(-2-x)​

Answer 1

Resposta:

$a) \: (4 - x) \times (3 {x}^{2} - 2x + 8) \\ 12 {x}^{2} - 8x + 32 - 3 {x}^{3} + 2 {x}^{2} - 8x \\ - 3 {x}^{3} + 14 {x}^{2} - 16x + 32$

$b) \: (2y - x) \times (4 + {x}^{2} ) \\ 8y + 2 {x}^{2} y - 4x - {x}^{3}$

$c) \: (3a + {b}^{4} ) \times ( - 4a - 5b) \\ - 12 {a}^{2} - 15ab - 4 {ab}^{4} - 5 {b}^{5}$

$d) \: (4 {x}^{3} + 3x + 1) \times ( - 2 - x) \\ - 8 {x}^{3} - 4 {x}^{4} - 6x - 3 {x}^{2} - 2 - x \\ - 4 {x}^{4} - 8 {x}^{3} - 3 {x}^{2} - 7x - 2$