Evaluate
\frac{\sqrt{2}}{2}\approx 0.707106781
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\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{\left(4+8\sqrt{2}\right)\left(4-8\sqrt{2}\right)}
Rationalize the denominator of \frac{8+2\sqrt{2}}{4+8\sqrt{2}} by multiplying numerator and denominator by 4-8\sqrt{2}.
\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{4^{2}-\left(8\sqrt{2}\right)^{2}}
Consider \left(4+8\sqrt{2}\right)\left(4-8\sqrt{2}\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{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{16-\left(8\sqrt{2}\right)^{2}}
Calculate 4 to the power of 2 and get 16.
\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{16-8^{2}\left(\sqrt{2}\right)^{2}}
Expand \left(8\sqrt{2}\right)^{2}.
\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{16-64\left(\sqrt{2}\right)^{2}}
Calculate 8 to the power of 2 and get 64.
\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{16-64\times 2}
The square of \sqrt{2} is 2.
\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{16-128}
Multiply 64 and 2 to get 128.
\frac{\left(8+2\sqrt{2}\right)\left(4-8\sqrt{2}\right)}{-112}
Subtract 128 from 16 to get -112.
\frac{32-64\sqrt{2}+8\sqrt{2}-16\left(\sqrt{2}\right)^{2}}{-112}
Apply the distributive property by multiplying each term of 8+2\sqrt{2} by each term of 4-8\sqrt{2}.
\frac{32-56\sqrt{2}-16\left(\sqrt{2}\right)^{2}}{-112}
Combine -64\sqrt{2} and 8\sqrt{2} to get -56\sqrt{2}.
\frac{32-56\sqrt{2}-16\times 2}{-112}
The square of \sqrt{2} is 2.
\frac{32-56\sqrt{2}-32}{-112}
Multiply -16 and 2 to get -32.
\frac{-56\sqrt{2}}{-112}
Subtract 32 from 32 to get 0.
\frac{1}{2}\sqrt{2}
Divide -56\sqrt{2} by -112 to get \frac{1}{2}\sqrt{2}.
Examples
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{ 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}