Question

cum se rezolva: (x+1)^2-9?

Answer 1

Răspuns:

uite aici...bafta la scoal!

Explicație pas cu pas:

Answer 2

(x+1)^2-9

(a+b)²=a²+2ab+b²

(x+1)²=x²+2x+1

x²+2x+1-9 = x²+2x-8

x²+2x-8=0

Δ=b²-4ac = 2²-4×1×(-8) = 4+32 = 36 > 0

x₁₂=-b±√Δ/2a = -2±√36/2 =( -2±6)/2

x₁=(-2+6)/2=4/2=2

x₂=(-2-6)/2=-8/2=-4

{2; -4}