Question

Resolva as equações do 2°:
a) x (x + 2) = 1
b) (x + 2)² = 4

Answer 1

a) x (x + 2) = 1
x² + 2x = 1
x² +2x -1 = 0
Δ=4+4
Δ=0

x¹ = -2+0/2= -1
x² = -2-0/2 = 1

b) (x + 2)² = 4
x²+2.x.2+2² = 4
x²+4x+4=4
x²+4x-0=0

Δ=16+0
Δ=16

x¹ = -4+4/2=0
x² = -4-4/2=4