Evaluate
-\frac{\left(n-8\right)\left(n+2\right)}{4}
Expand
-\frac{n^{2}}{4}+\frac{3n}{2}+4
Share
Copied to clipboard
\frac{1}{2}\left(\frac{8\times 2}{2n}-\frac{\left(n-6\right)n}{2n}\right)n
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of n and 2 is 2n. Multiply \frac{8}{n} times \frac{2}{2}. Multiply \frac{n-6}{2} times \frac{n}{n}.
\frac{1}{2}\times \frac{8\times 2-\left(n-6\right)n}{2n}n
Since \frac{8\times 2}{2n} and \frac{\left(n-6\right)n}{2n} have the same denominator, subtract them by subtracting their numerators.
\frac{1}{2}\times \frac{16-n^{2}+6n}{2n}n
Do the multiplications in 8\times 2-\left(n-6\right)n.
\frac{16-n^{2}+6n}{2\times 2n}n
Multiply \frac{1}{2} times \frac{16-n^{2}+6n}{2n} by multiplying numerator times numerator and denominator times denominator.
\frac{\left(16-n^{2}+6n\right)n}{2\times 2n}
Express \frac{16-n^{2}+6n}{2\times 2n}n as a single fraction.
\frac{-n^{2}+6n+16}{2\times 2}
Cancel out n in both numerator and denominator.
\frac{-n^{2}+6n+16}{4}
Multiply 2 and 2 to get 4.
\frac{1}{2}\left(\frac{8\times 2}{2n}-\frac{\left(n-6\right)n}{2n}\right)n
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of n and 2 is 2n. Multiply \frac{8}{n} times \frac{2}{2}. Multiply \frac{n-6}{2} times \frac{n}{n}.
\frac{1}{2}\times \frac{8\times 2-\left(n-6\right)n}{2n}n
Since \frac{8\times 2}{2n} and \frac{\left(n-6\right)n}{2n} have the same denominator, subtract them by subtracting their numerators.
\frac{1}{2}\times \frac{16-n^{2}+6n}{2n}n
Do the multiplications in 8\times 2-\left(n-6\right)n.
\frac{16-n^{2}+6n}{2\times 2n}n
Multiply \frac{1}{2} times \frac{16-n^{2}+6n}{2n} by multiplying numerator times numerator and denominator times denominator.
\frac{\left(16-n^{2}+6n\right)n}{2\times 2n}
Express \frac{16-n^{2}+6n}{2\times 2n}n as a single fraction.
\frac{-n^{2}+6n+16}{2\times 2}
Cancel out n in both numerator and denominator.
\frac{-n^{2}+6n+16}{4}
Multiply 2 and 2 to get 4.
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}