求满足下列各式的x的值(1)x^2=1.21(2)x^3=-0.125(3)(x-1)^2=4(4)8(2x+1)^3-27=0

问题描述:

求满足下列各式的x的值(1)x^2=1.21(2)x^3=-0.125(3)(x-1)^2=4(4)8(2x+1)^3-27=0

1 、x=1.1和x=-1.1
2 、x=-0.5
3、 x=3或x=-1(x-1)^2=4=>x-1=2或x-1=-2所以 答案x=3或x=-1
4、 x=1/4 8(2x+1)^3=27=>2(2x+1)=3 => 2x+1=3/2解得前面答案
应该不用求复数的吧?