Question

(x-1)⁴ - 8(x-1)² - 9 = 0

 

Answer 1

(x-1)^2=t, тогда

t^2-8t-9=0

D=64+36=100

Корень из D равен 10

t1=8+10/2=9, t2=8-10/2=-1

Answer 2

(x-1)⁴ - 8(x-1)² - 9 = 0

 x^4+1-8(x^2-2x+1)-9=0

x^4+1-8x^2+16x-8-9=0

x^4-8x^2+16x-16=0

x^2(x^2-8)+4(4x-4)=0