求下列x的值:①4x²-9=0;②8x³+27=0;③1/2(x+1)²-8=0;④4(2x-1)³-64=0.
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/23 08:57:33
![求下列x的值:①4x²-9=0;②8x³+27=0;③1/2(x+1)²-8=0;④4(2x-1)³-64=0.](/uploads/image/z/12930366-30-6.jpg?t=%E6%B1%82%E4%B8%8B%E5%88%97x%E7%9A%84%E5%80%BC%EF%BC%9A%E2%91%A04x%26%23178%3B-9%3D0%EF%BC%9B%E2%91%A18x%26%23179%3B%2B27%3D0%EF%BC%9B%E2%91%A21%2F2%EF%BC%88x%2B1%EF%BC%89%26%23178%3B-8%3D0%EF%BC%9B%E2%91%A34%EF%BC%882x-1%EF%BC%89%26%23179%3B-64%3D0.)
求下列x的值:①4x²-9=0;②8x³+27=0;③1/2(x+1)²-8=0;④4(2x-1)³-64=0.
求下列x的值:
①4x²-9=0;
②8x³+27=0;
③1/2(x+1)²-8=0;
④4(2x-1)³-64=0.
求下列x的值:①4x²-9=0;②8x³+27=0;③1/2(x+1)²-8=0;④4(2x-1)³-64=0.
(1)
(2x)^2=9
2x=±3
x=±3/2
(2)
(2x)^3=-27
2x=-3
x=-3/2
(3)
1/2(x+1)^2=8
(x+1)^2=16
x+1=±4
x1=-5,x2=3
(4)
4(2x-1)^3=64
(2x-1)^3=16
2x-1=16^(1/3)
2x=1+2×2^(1/3)
x=2^(1/3)+1/2
1. 4x²=9 x=±3/2
2.8x³=-27 x=﹣3/2
3.(x+1)²=16 x1=3 x2=-5
4.(2x-1)³=(³√16)/2+1/2
①4x²-9=0;
4x²=9
x²=9/4
x=3/2 或x-=3/2
②8x³+27=0;
x³=-27/8
x³=-3/2
③1/2(x+1)²-8=0;
(x+1)²=16
x+1=4或x+1=-4
x=3或x=-5
④4...
全部展开
①4x²-9=0;
4x²=9
x²=9/4
x=3/2 或x-=3/2
②8x³+27=0;
x³=-27/8
x³=-3/2
③1/2(x+1)²-8=0;
(x+1)²=16
x+1=4或x+1=-4
x=3或x=-5
④4(2x-1)³-64=0。
收起