30/x=30/(x-1.5)-x
问题描述：
30/x=30/(x-1.5)-x
答
200
答
30/x=30/(x-1.5)-x
30(x-1.5)=30x-x^2(x-1.5)
30x-45=30x-x^3+1.5x^2
x^3-1.5x^2-45=0
2x^3-3x^2-90=0