Question

Resolva

a) 4 x 2 + 8 x+6 = 0 b) x²₋ 4 x -5 = 0



c) x²₋ 6 x +5 =0 d) x² ⁻ 3 x -4 = 0


Valendo 54pts

Answer 1

Resposta:

a)4x2+8x+6=0

2x2+4x+3=0

x=(-4+-v[4^2-4×2×3])/2×2

x=(-4+-v[-8])/4

x ∉ ℝ

b)x²-4x-5=0

x(x+1)-5(x+1)=0

x+1=0 x=-1

x-5=0 x=5

s=(-1, 5)

c)x²-6x+5=0

x(x-1)-5(x-1)=0

x-1=0 x=1

x-5=0 x=5

s=(1, 5)

d)x²-3x-4=0

x(x+1)-4(x+1)

x+1=0 x=-1

x-4=0 x=4

s=(-1, 4).