Question

1) Desenvolva os produtos notáveis. a) (x + 1)2 = b) (2x + 3)2 = c) (5x – 3y)2 = d) (x + 7).(x – 7) = e) (3x – 5).(3x + 5) = f) (x – 5).(x + 9) = g) (x – 8).(x – 2) =

Answer 1

Resposta:

a.

$(x + 1)^{2} =\\x^{2} + 2.1.x + 1\\ x^{2} + 2x + 1$

b.

$(2x + 3)^{2} =\\4x^{2} + 2.3.2x + 9 =\\4x^{2} + 12x + 9$

c.

$(5x - 3y)^{2} =\\25x^{2} - 2.5x.3y + 9y^{2} =\\25x^{2} - 30xy + 9y^{2}$

d.

$(x + 7)(x - 7) =\\x^{2} - 49.$

e.

$(3x - 5)(3x + 5) =\\9x^{2} - 25$

f.

$(x - 5). (x + 9) =\\x^{2} + 4x - 45$

g.

$(x - 8)(x - 2) =\\x^{2} - 10x + 16$