8(3-x)²-72=0 5x²-3x+2=0

问题描述:

8(3-x)²-72=0 5x²-3x+2=0

8(3-x)²-72=0
(x-3)²=9
x-3=±3
x=0,x=6
5x²-3x+2=0
判别式小于0,无解
若是5x²-3x-2=0
(5x+2)(x-1)=0
x=-2/5,x=1