Factor
a\left(9a-b\right)\left(9a+b\right)
Evaluate
a\left(81a^{2}-b^{2}\right)
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a\left(81a^{2}-b^{2}\right)
Factor out a.
\left(9a-b\right)\left(9a+b\right)
Consider 81a^{2}-b^{2}. Rewrite 81a^{2}-b^{2} as \left(9a\right)^{2}-b^{2}. The difference of squares can be factored using the rule: p^{2}-q^{2}=\left(p-q\right)\left(p+q\right).
a\left(9a-b\right)\left(9a+b\right)
Rewrite the complete factored expression.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
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Linear equation
y = 3x + 4
Arithmetic
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Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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