Evaluate
\frac{\sqrt{78}}{2}-\frac{\sqrt{2}}{15}\approx 4.321599529
Factor
\frac{15 \sqrt{78} - 2 \sqrt{2}}{30} = 4.321599529005718
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3\sqrt{\frac{16}{6}-\frac{3}{6}}-\frac{\sqrt{2}}{15}
Least common multiple of 3 and 2 is 6. Convert \frac{8}{3} and \frac{1}{2} to fractions with denominator 6.
3\sqrt{\frac{16-3}{6}}-\frac{\sqrt{2}}{15}
Since \frac{16}{6} and \frac{3}{6} have the same denominator, subtract them by subtracting their numerators.
3\sqrt{\frac{13}{6}}-\frac{\sqrt{2}}{15}
Subtract 3 from 16 to get 13.
3\times \frac{\sqrt{13}}{\sqrt{6}}-\frac{\sqrt{2}}{15}
Rewrite the square root of the division \sqrt{\frac{13}{6}} as the division of square roots \frac{\sqrt{13}}{\sqrt{6}}.
3\times \frac{\sqrt{13}\sqrt{6}}{\left(\sqrt{6}\right)^{2}}-\frac{\sqrt{2}}{15}
Rationalize the denominator of \frac{\sqrt{13}}{\sqrt{6}} by multiplying numerator and denominator by \sqrt{6}.
3\times \frac{\sqrt{13}\sqrt{6}}{6}-\frac{\sqrt{2}}{15}
The square of \sqrt{6} is 6.
3\times \frac{\sqrt{78}}{6}-\frac{\sqrt{2}}{15}
To multiply \sqrt{13} and \sqrt{6}, multiply the numbers under the square root.
\frac{\sqrt{78}}{2}-\frac{\sqrt{2}}{15}
Cancel out 6, the greatest common factor in 3 and 6.
\frac{15\sqrt{78}}{30}-\frac{2\sqrt{2}}{30}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 2 and 15 is 30. Multiply \frac{\sqrt{78}}{2} times \frac{15}{15}. Multiply \frac{\sqrt{2}}{15} times \frac{2}{2}.
\frac{15\sqrt{78}-2\sqrt{2}}{30}
Since \frac{15\sqrt{78}}{30} and \frac{2\sqrt{2}}{30} have the same denominator, subtract them by subtracting their numerators.
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}