7/x^2+x-2/x-x^3=6/x^2-1
7/x^2 + (x-2)/x(1-x^2)=6/(x^2-1)
7/x^2 - (x-2)/x(x^2-1)=6/(x^2-1)
7(x^2-1) - x(x-2)=6x^2
7x^2-7 - x^2+2x=6x^2
x=7/2
经检验x=7/2是方程的解
7/x^2+x-2/x-x^3=6/x^2-1
7/x^2 + (x-2)/x(1-x^2)=6/(x^2-1)
7/x^2 - (x-2)/x(x^2-1)=6/(x^2-1)
7(x^2-1) - x(x-2)=6x^2
7x^2-7 - x^2+2x=6x^2
x=7/2
经检验x=7/2是方程的解