已知x-1^2=4,则x= ,1X3(x+1)^3=-64,则x=
问题描述:
已知x-1^2=4,则x= ,1X3(x+1)^3=-64,则x=
.
答
(x-1)^2=4,x-1=±2,x=3或-1
x^3(x+1)^3=-64
[x(x+1)]^3=-64
x(x+1)=-4
x^2+x+4=0
△=1-16=-15