Evaluate
\frac{6\sqrt{7}}{7}-5\approx -2.732213162
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2\times \frac{\sqrt{9}}{\sqrt{5.4+1.6}}-5
Subtract 8 from 17 to get 9.
2\times \frac{3}{\sqrt{5.4+1.6}}-5
Calculate the square root of 9 and get 3.
2\times \frac{3}{\sqrt{7}}-5
Add 5.4 and 1.6 to get 7.
2\times \frac{3\sqrt{7}}{\left(\sqrt{7}\right)^{2}}-5
Rationalize the denominator of \frac{3}{\sqrt{7}} by multiplying numerator and denominator by \sqrt{7}.
2\times \frac{3\sqrt{7}}{7}-5
The square of \sqrt{7} is 7.
\frac{2\times 3\sqrt{7}}{7}-5
Express 2\times \frac{3\sqrt{7}}{7} as a single fraction.
\frac{2\times 3\sqrt{7}}{7}-\frac{5\times 7}{7}
To add or subtract expressions, expand them to make their denominators the same. Multiply 5 times \frac{7}{7}.
\frac{2\times 3\sqrt{7}-5\times 7}{7}
Since \frac{2\times 3\sqrt{7}}{7} and \frac{5\times 7}{7} have the same denominator, subtract them by subtracting their numerators.
\frac{6\sqrt{7}-35}{7}
Do the multiplications in 2\times 3\sqrt{7}-5\times 7.
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}