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\frac{3n}{m+n}
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\frac{3n}{m+n}
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\frac{\frac{m+n}{\left(m+n\right)\left(m-n\right)}-\frac{m-n}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of m-n and m+n is \left(m+n\right)\left(m-n\right). Multiply \frac{1}{m-n} times \frac{m+n}{m+n}. Multiply \frac{1}{m+n} times \frac{m-n}{m-n}.
\frac{\frac{m+n-\left(m-n\right)}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
Since \frac{m+n}{\left(m+n\right)\left(m-n\right)} and \frac{m-n}{\left(m+n\right)\left(m-n\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{\frac{m+n-m+n}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
Do the multiplications in m+n-\left(m-n\right).
\frac{\frac{2n}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
Combine like terms in m+n-m+n.
\frac{2n\left(3m-3n\right)}{\left(m+n\right)\left(m-n\right)\times 2}
Divide \frac{2n}{\left(m+n\right)\left(m-n\right)} by \frac{2}{3m-3n} by multiplying \frac{2n}{\left(m+n\right)\left(m-n\right)} by the reciprocal of \frac{2}{3m-3n}.
\frac{n\left(3m-3n\right)}{\left(m+n\right)\left(m-n\right)}
Cancel out 2 in both numerator and denominator.
\frac{3n\left(m-n\right)}{\left(m+n\right)\left(m-n\right)}
Factor the expressions that are not already factored.
\frac{3n}{m+n}
Cancel out m-n in both numerator and denominator.
\frac{\frac{m+n}{\left(m+n\right)\left(m-n\right)}-\frac{m-n}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of m-n and m+n is \left(m+n\right)\left(m-n\right). Multiply \frac{1}{m-n} times \frac{m+n}{m+n}. Multiply \frac{1}{m+n} times \frac{m-n}{m-n}.
\frac{\frac{m+n-\left(m-n\right)}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
Since \frac{m+n}{\left(m+n\right)\left(m-n\right)} and \frac{m-n}{\left(m+n\right)\left(m-n\right)} have the same denominator, subtract them by subtracting their numerators.
\frac{\frac{m+n-m+n}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
Do the multiplications in m+n-\left(m-n\right).
\frac{\frac{2n}{\left(m+n\right)\left(m-n\right)}}{\frac{2}{3m-3n}}
Combine like terms in m+n-m+n.
\frac{2n\left(3m-3n\right)}{\left(m+n\right)\left(m-n\right)\times 2}
Divide \frac{2n}{\left(m+n\right)\left(m-n\right)} by \frac{2}{3m-3n} by multiplying \frac{2n}{\left(m+n\right)\left(m-n\right)} by the reciprocal of \frac{2}{3m-3n}.
\frac{n\left(3m-3n\right)}{\left(m+n\right)\left(m-n\right)}
Cancel out 2 in both numerator and denominator.
\frac{3n\left(m-n\right)}{\left(m+n\right)\left(m-n\right)}
Factor the expressions that are not already factored.
\frac{3n}{m+n}
Cancel out m-n in both numerator and denominator.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
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
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}