`(3x^2-7x-2)/(x^3-x)=(3x^2-7x-2)/[x(x+1)(x-1)]`
`(3x^2-7x-2)/(x^3-x)=A/x+B/(x+1)+C/(x-1)`
Multiply through by the LDC `x^3-x.`
`3x^2-7x-2=A(x^2-1)+Bx(x-1)+Cx(x+1)`
`3x^2-7x-2=Ax^2-A+Bx^2-Bx+Cx^2+Cx`
`3x^2-7x-2=(A+B+C)x^2+(-B+C)x-A`
Equate the coefficients of like terms. Then solve for A, B, and C.
`3=A+B+C`
`-7=-B+C`
`-2=-A`
`A=2`
`3=A+B+C`
`3=2+B+C`
`1=B+C`
Use the elimination method to solve for B and C.
`1=B+C`
`-7=-B+C`
_______________
`-6=2C`
`-3=C`
`1=B+C`
`1=B-3`
`4=B`
`A=2, B=4, C=-3`
`(3x^2-7x-2)/(x^3-x)=2/x+4/(x+1)-3/(x-1)`
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