Evaluate
-\frac{21}{8}=-2.625
Factor
-\frac{21}{8} = -2\frac{5}{8} = -2.625
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-\frac{1}{8}+\frac{\left(-\frac{2}{5}\right)^{2}}{-\frac{8}{125}}
Calculate -\frac{1}{2} to the power of 3 and get -\frac{1}{8}.
-\frac{1}{8}+\frac{\frac{4}{25}}{-\frac{8}{125}}
Calculate -\frac{2}{5} to the power of 2 and get \frac{4}{25}.
-\frac{1}{8}+\frac{4}{25}\left(-\frac{125}{8}\right)
Divide \frac{4}{25} by -\frac{8}{125} by multiplying \frac{4}{25} by the reciprocal of -\frac{8}{125}.
-\frac{1}{8}+\frac{4\left(-125\right)}{25\times 8}
Multiply \frac{4}{25} times -\frac{125}{8} by multiplying numerator times numerator and denominator times denominator.
-\frac{1}{8}+\frac{-500}{200}
Do the multiplications in the fraction \frac{4\left(-125\right)}{25\times 8}.
-\frac{1}{8}-\frac{5}{2}
Reduce the fraction \frac{-500}{200} to lowest terms by extracting and canceling out 100.
-\frac{1}{8}-\frac{20}{8}
Least common multiple of 8 and 2 is 8. Convert -\frac{1}{8} and \frac{5}{2} to fractions with denominator 8.
\frac{-1-20}{8}
Since -\frac{1}{8} and \frac{20}{8} have the same denominator, subtract them by subtracting their numerators.
-\frac{21}{8}
Subtract 20 from -1 to get -21.
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}