Question

Rozwiąż równania

6x2+x-1=0

X3-2x2-9x+18=0

Answer 1

a)

6x²+x-1=0

Δ=1²-4*6*(-1)=1+24=25

√Δ=5

x₁=(-1+5)/12=4/12=⅓

x₂=(-1-5)/12=-6/12=-½

 

b)

X³-2x²-9x+18=0

x²(x-2)-9(x-2)=0

(x-2)(x²-9)=0

(x-2)(x-3)(x+3)=0

x=2 ∨ x=3 ∨ x=-3