Evaluate
-\frac{2\sqrt{2}}{5}-\frac{8\sqrt{3}}{15}\approx -1.489445856
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\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{\left(3-2\sqrt{6}\right)\left(3+2\sqrt{6}\right)}
Rationalize the denominator of \frac{2\sqrt{2}}{3-2\sqrt{6}} by multiplying numerator and denominator by 3+2\sqrt{6}.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{3^{2}-\left(-2\sqrt{6}\right)^{2}}
Consider \left(3-2\sqrt{6}\right)\left(3+2\sqrt{6}\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{9-\left(-2\sqrt{6}\right)^{2}}
Calculate 3 to the power of 2 and get 9.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{9-\left(-2\right)^{2}\left(\sqrt{6}\right)^{2}}
Expand \left(-2\sqrt{6}\right)^{2}.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{9-4\left(\sqrt{6}\right)^{2}}
Calculate -2 to the power of 2 and get 4.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{9-4\times 6}
The square of \sqrt{6} is 6.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{9-24}
Multiply 4 and 6 to get 24.
\frac{2\sqrt{2}\left(3+2\sqrt{6}\right)}{-15}
Subtract 24 from 9 to get -15.
\frac{6\sqrt{2}+4\sqrt{2}\sqrt{6}}{-15}
Use the distributive property to multiply 2\sqrt{2} by 3+2\sqrt{6}.
\frac{6\sqrt{2}+4\sqrt{2}\sqrt{2}\sqrt{3}}{-15}
Factor 6=2\times 3. Rewrite the square root of the product \sqrt{2\times 3} as the product of square roots \sqrt{2}\sqrt{3}.
\frac{6\sqrt{2}+4\times 2\sqrt{3}}{-15}
Multiply \sqrt{2} and \sqrt{2} to get 2.
\frac{6\sqrt{2}+8\sqrt{3}}{-15}
Multiply 4 and 2 to get 8.
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}