Evaluate
4\left(\sqrt{5}+2\right)\approx 16.94427191
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\frac{4\left(\sqrt{5}+2\right)}{\left(\sqrt{5}-2\right)\left(\sqrt{5}+2\right)}
Rationalize the denominator of \frac{4}{\sqrt{5}-2} by multiplying numerator and denominator by \sqrt{5}+2.
\frac{4\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{4\left(\sqrt{5}+2\right)}{5-4}
Square \sqrt{5}. Square 2.
\frac{4\left(\sqrt{5}+2\right)}{1}
Subtract 4 from 5 to get 1.
4\left(\sqrt{5}+2\right)
Anything divided by one gives itself.
4\sqrt{5}+8
Use the distributive property to multiply 4 by \sqrt{5}+2.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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