Evaluate
\frac{9x}{x^{2}-9}
Factor
\frac{9x}{x^{2}-9}
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\frac{x^{3}}{\left(x-3\right)\left(x+3\right)}-x
Factor x^{2}-9.
\frac{x^{3}}{\left(x-3\right)\left(x+3\right)}-\frac{x\left(x-3\right)\left(x+3\right)}{\left(x-3\right)\left(x+3\right)}
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{\left(x-3\right)\left(x+3\right)}{\left(x-3\right)\left(x+3\right)}.
\frac{x^{3}-x\left(x-3\right)\left(x+3\right)}{\left(x-3\right)\left(x+3\right)}
Since \frac{x^{3}}{\left(x-3\right)\left(x+3\right)} and \frac{x\left(x-3\right)\left(x+3\right)}{\left(x-3\right)\left(x+3\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{x^{3}-x^{3}-3x^{2}+3x^{2}+9x}{\left(x-3\right)\left(x+3\right)}
Do the multiplications in x^{3}-x\left(x-3\right)\left(x+3\right).
\frac{9x}{\left(x-3\right)\left(x+3\right)}
Combine like terms in x^{3}-x^{3}-3x^{2}+3x^{2}+9x.
\frac{9x}{x^{2}-9}
Expand \left(x-3\right)\left(x+3\right).
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}