Evaluate
\frac{n\left(n+1\right)}{2}
Expand
\frac{n^{2}+n}{2}
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\frac{n\left(n+1\right)}{2}
Express \frac{n}{2}\left(n+1\right) as a single fraction.
\frac{n^{2}+n}{2}
Use the distributive property to multiply n by n+1.
\frac{n\left(n+1\right)}{2}
Express \frac{n}{2}\left(n+1\right) as a single fraction.
\frac{n^{2}+n}{2}
Use the distributive property to multiply n by n+1.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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