How do you simplify \frac { x + 2} { ( x - 3) ( x + 1) } + \frac { x ( x - 2) } { 3( x - 3) } + \frac { 1- x ^ { 3} } { 3( x ^ { 2} - 2x - 3) } = - \frac { x } { 3( x + 1) }?

1 Answer
Jul 7, 2018

x=7/2

Explanation:

(x+2)/((x-3)(x+1))+(x(x-2))/(3*(x-3))+(1-x^3)/(3*(x^2-2x-3))=-x/(3*(x+1))

(3*(x+2)+x(x-2)(x+1)+1-x^3)/(3*(x^2-2x-3))=-x/(3*(x+1))

(3x+6+x^3-x^2-2x+1-x^3)/(3*(x^2-2x-3))=-x/(3*(x+1))

(-x^2+x+7)/(3*(x^2-2x-3))=-x/(3*(x+1))

(-x^2+x+7)/(x^2-2x-3)=-x/(x+1)

-(x^2-x-7)/((x+1)*(x-3))=-x/(x+1)

(x^2-x-7)/((x+1)*(x-3))=x/(x+1)

x^2-x-7=x*(x-3)

x^2-x-7=x^2-3x

2x=7, so x=7/2