Question

determine os produtos
e) (2x + 4)(x - 1)
f) (x + 6) (x + 6)
g) (x + 2)(x - 2)
h) (x + 1)(2x3 – 5x + 4)
i) (x + 4)(x2 – x + 3)
j) (x – 3)(x2 – 2x + 1)​

Answer 1

Oie, Td Bom?!

e)

$= (2x + 4) \: . \: (x - 1)$

$= 2x \: . \: (x - 1) + 4(x - 1)$

$= 2x {}^{2} - 2 x + 4x - 4$

$= 2x {}^{2} + 2x - 4$

f)

$= (x + 6) \: . \: (x + 6)$

$= x \: . \: (x + 6) + 6(x + 6)$

$= x {}^{2} + 6x + 6x + 36$

$= x {}^{2} + 12x + 36$

g)

$= (x + 2) \: . \: (x - 2)$

$= x \: . \: (x - 2) + 2(x - 2)$

$= x {}^{2} - 2x + 2x - 4$

$= x {}^{2} - 4$

h)

$= (x + 1) \: . \: (2x {}^{3} - 5x + 4)$

$= x \: . \: (2x {}^{3} - 5x + 4) + 1(2x {}^{3} - 5x + 4)$

$= 2x {}^{4} - 5x {}^{2} + 4x + 2x {}^{3} - 5x + 4$

$= 2x {}^{4} - 5x {}^{2} - x + 2x {}^{3} + 4$

$= 2x {}^{4} + 2x {}^{3} - 5x {}^{2} - x + 4$

i)

$= (x + 4) \: . \: (x {}^{2} - x + 3)$

$= x \: . \: (x {}^{2} - x + 3) + 4(x {}^{2} - x + 3)$

$= x {}^{3} - x {}^{2} + 3x + 4x {}^{2} - 4x + 12$

$= x {}^{3} + 3x {}^{2} - x + 12$

j)

$= (x - 3) \: . \: (x {}^{2} - 2x + 1)$

$= x \: . \: (x {}^{2} - 2x + 1) - 3(x {}^{2} - 2x + 1)$

$= x {}^{3} - 2x {}^{2} + x - 3x {}^{2} + 6x - 3$

$= x {}^{3} - 5x {}^{2} + 7x - 3$

Att. Makaveli1996