Evaluate
\frac{18-54\sqrt{3}}{13}\approx -5.810057201
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\frac{-36\times 2}{2+2\sqrt{27}}
Calculate 6 to the power of 2 and get 36.
\frac{-72}{2+2\sqrt{27}}
Multiply -36 and 2 to get -72.
\frac{-72}{2+2\times 3\sqrt{3}}
Factor 27=3^{2}\times 3. Rewrite the square root of the product \sqrt{3^{2}\times 3} as the product of square roots \sqrt{3^{2}}\sqrt{3}. Take the square root of 3^{2}.
\frac{-72}{2+6\sqrt{3}}
Multiply 2 and 3 to get 6.
\frac{-72\left(2-6\sqrt{3}\right)}{\left(2+6\sqrt{3}\right)\left(2-6\sqrt{3}\right)}
Rationalize the denominator of \frac{-72}{2+6\sqrt{3}} by multiplying numerator and denominator by 2-6\sqrt{3}.
\frac{-72\left(2-6\sqrt{3}\right)}{2^{2}-\left(6\sqrt{3}\right)^{2}}
Consider \left(2+6\sqrt{3}\right)\left(2-6\sqrt{3}\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{-72\left(2-6\sqrt{3}\right)}{4-\left(6\sqrt{3}\right)^{2}}
Calculate 2 to the power of 2 and get 4.
\frac{-72\left(2-6\sqrt{3}\right)}{4-6^{2}\left(\sqrt{3}\right)^{2}}
Expand \left(6\sqrt{3}\right)^{2}.
\frac{-72\left(2-6\sqrt{3}\right)}{4-36\left(\sqrt{3}\right)^{2}}
Calculate 6 to the power of 2 and get 36.
\frac{-72\left(2-6\sqrt{3}\right)}{4-36\times 3}
The square of \sqrt{3} is 3.
\frac{-72\left(2-6\sqrt{3}\right)}{4-108}
Multiply 36 and 3 to get 108.
\frac{-72\left(2-6\sqrt{3}\right)}{-104}
Subtract 108 from 4 to get -104.
\frac{9}{13}\left(2-6\sqrt{3}\right)
Divide -72\left(2-6\sqrt{3}\right) by -104 to get \frac{9}{13}\left(2-6\sqrt{3}\right).
\frac{9}{13}\times 2+\frac{9}{13}\left(-6\right)\sqrt{3}
Use the distributive property to multiply \frac{9}{13} by 2-6\sqrt{3}.
\frac{9\times 2}{13}+\frac{9}{13}\left(-6\right)\sqrt{3}
Express \frac{9}{13}\times 2 as a single fraction.
\frac{18}{13}+\frac{9}{13}\left(-6\right)\sqrt{3}
Multiply 9 and 2 to get 18.
\frac{18}{13}+\frac{9\left(-6\right)}{13}\sqrt{3}
Express \frac{9}{13}\left(-6\right) as a single fraction.
\frac{18}{13}+\frac{-54}{13}\sqrt{3}
Multiply 9 and -6 to get -54.
\frac{18}{13}-\frac{54}{13}\sqrt{3}
Fraction \frac{-54}{13} can be rewritten as -\frac{54}{13} by extracting the negative sign.
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}