Question

2x ^ 4 - 5x ^ 3 + 4x ^ 2 - 5x + 2 = 0

Answer 1

делить x^2

2x^2-5x+4-5/x+2/x^2=0

2(x^2+1/x^2)-5(x+1/x)+4=0

x+1/x=t

2(t^2-2)-5t+4=0

2t^2-5t=0

t(2t-5)=0

t=0

2t=5

t=2,5

x+1/x=0

x^2+1=0

x - нету корней

x+1/x=2,5

x^2-2,5x+1=0

2x^2-5x+2=0

D=9

x=(5+-3)/4=2; 0,5