Evaluate
-\frac{20\sqrt{7}}{7}\approx -7.55928946
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-5\sqrt{\frac{14+2}{7}}
Multiply 2 and 7 to get 14.
-5\sqrt{\frac{16}{7}}
Add 14 and 2 to get 16.
-5\times \frac{\sqrt{16}}{\sqrt{7}}
Rewrite the square root of the division \sqrt{\frac{16}{7}} as the division of square roots \frac{\sqrt{16}}{\sqrt{7}}.
-5\times \frac{4}{\sqrt{7}}
Calculate the square root of 16 and get 4.
-5\times \frac{4\sqrt{7}}{\left(\sqrt{7}\right)^{2}}
Rationalize the denominator of \frac{4}{\sqrt{7}} by multiplying numerator and denominator by \sqrt{7}.
-5\times \frac{4\sqrt{7}}{7}
The square of \sqrt{7} is 7.
\frac{-5\times 4\sqrt{7}}{7}
Express -5\times \frac{4\sqrt{7}}{7} as a single fraction.
\frac{-20\sqrt{7}}{7}
Multiply -5 and 4 to get -20.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}