Evaluate
\sqrt{3}\left(\sqrt{5}-2\right)\approx 0.408881731
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\frac{\sqrt{3}\left(\sqrt{5}-2\right)}{\left(\sqrt{5}+2\right)\left(\sqrt{5}-2\right)}
Rationalize the denominator of \frac{\sqrt{3}}{\sqrt{5}+2} by multiplying numerator and denominator by \sqrt{5}-2.
\frac{\sqrt{3}\left(\sqrt{5}-2\right)}{\left(\sqrt{5}\right)^{2}-2^{2}}
Consider \left(\sqrt{5}+2\right)\left(\sqrt{5}-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{\sqrt{3}\left(\sqrt{5}-2\right)}{5-4}
Square \sqrt{5}. Square 2.
\frac{\sqrt{3}\left(\sqrt{5}-2\right)}{1}
Subtract 4 from 5 to get 1.
\sqrt{3}\left(\sqrt{5}-2\right)
Anything divided by one gives itself.
\sqrt{3}\sqrt{5}-2\sqrt{3}
Use the distributive property to multiply \sqrt{3} by \sqrt{5}-2.
\sqrt{15}-2\sqrt{3}
To multiply \sqrt{3} and \sqrt{5}, multiply the numbers under the square root.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
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y = 3x + 4
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Matrix
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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}