1) 2x³-x²-1=0
2x³-2x²+x²-1=0
(x-1)*(2x²+x+1)=0
x-1=0 2x²+x+1=0
x=1 D=(1)²-4*2*1=-6
D≠-6 t.k. D<0<br>
Otvet: x=1
3) x⁴+x³+x²-x-2=0
(x-1)*(x³+2x²+3x+2)=0
(x-1)*(x+1)*(x²+x+2)=0
x-1=0 x+1=0 x²+x+2=0
x₁=1 x₂=-1 D=(1)²-4*1*2=-5
D≠5 t.k. D<0<br>
Otvet: x₁=1 ; x₂=-1