The problem requires us to simplify the expression $\frac{8}{4y-y^3} + \frac{1}{y+2} - \frac{1}{y}$.

AlgebraAlgebraic simplificationRational expressionsFactoring
2025/4/25

1. Problem Description

The problem requires us to simplify the expression 84yy3+1y+21y\frac{8}{4y-y^3} + \frac{1}{y+2} - \frac{1}{y}.

2. Solution Steps

First, factor the denominator of the first term:
4yy3=y(4y2)=y(2y)(2+y)=y(y2)(y+2)4y - y^3 = y(4-y^2) = y(2-y)(2+y) = -y(y-2)(y+2)
The expression becomes:
8y(y2)(y+2)+1y+21y\frac{8}{-y(y-2)(y+2)} + \frac{1}{y+2} - \frac{1}{y}
Now, find a common denominator, which is y(y2)(y+2)-y(y-2)(y+2). Rewrite each term with the common denominator:
8y(y2)(y+2)+y(y2)(y+2)(y(y2))(y2)(y+2)y(1)(y2)(y+2)\frac{8}{-y(y-2)(y+2)} + \frac{-y(y-2)}{(y+2)(-y(y-2))} - \frac{-(y-2)(y+2)}{y(-1)(y-2)(y+2)}
8y(y2)(y+2)+y(y2)y(y2)(y+2)(y24)y(y2)(y+2)\frac{8}{-y(y-2)(y+2)} + \frac{-y(y-2)}{-y(y-2)(y+2)} - \frac{-(y^2-4)}{-y(y-2)(y+2)}
Combine the numerators:
8y(y2)+(y24)y(y2)(y+2)=8y2+2y+y24y(y2)(y+2)\frac{8 -y(y-2) + (y^2-4)}{-y(y-2)(y+2)} = \frac{8 - y^2 + 2y + y^2 - 4}{-y(y-2)(y+2)}
Simplify the numerator:
4+2yy(y2)(y+2)=2(2+y)y(y2)(y+2)\frac{4 + 2y}{-y(y-2)(y+2)} = \frac{2(2+y)}{-y(y-2)(y+2)}
Cancel the common factor (y+2)(y+2):
2y(y2)=2y2+2y=22yy2\frac{2}{-y(y-2)} = \frac{2}{-y^2+2y} = \frac{2}{2y-y^2}

3. Final Answer

22yy2\frac{2}{2y-y^2}

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