Question

determine os produtos notáveis
a) (x+4) . (3x+5)
b) (x+3) . (-3x+7)
c) (x+5) . (-x+2)
d) (2x+6) . (7x+4)
e) (7x+4) . (-4x+8)
f) (x-1) . (2x-3)
g) (4x+4) . (2x-5)
h) (6x+4) . (2x-5)
i) (9x+5) . (-6x+8)


URGENTEEEEE​

Answer 1

Resposta:

a)

$(x+4).(3x+5)\\x.3x+5x+4.3x+4.5\\3x^{2} +5x+12x+20\\=3x^{2}  +17x+20$

b)

$(x+3).(-3x+7)\\-x.3x+7x-3.3x+3.7\\-3x^{2} +7x-9x+21\\\\ =-3x^{2} -2x+21$

c)

$(x+5).(-x+2)\\-x.x+2x-5x+5x+5.2\\-x^{2} +2x-5x+10\\-x^{2} +2x-5x+10\\= -x^{2}-3x+10$

d)

$(2x+6).(7x+4)\\2x.7x+2x.4+6.7x+6.4\\14x^{2} +8x+42+24\\=14x^{2} +50x+24$

e)

$(7x+4).(-4x+8)\\-7x.4x+7x.8-4.4x+4.8\\-28x^{2} +56x-16x+32\\=-28x^{2} +40x+32$

Explicação passo-a-passo: