Evaluate
40-16\sqrt{5}\approx 4.22291236
Factor
8 \sqrt{5} {(\sqrt{5} - 2)} = 4.22291236
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30-6\sqrt{5}-10\sqrt{5}+2\left(\sqrt{5}\right)^{2}
Apply the distributive property by multiplying each term of 6-2\sqrt{5} by each term of 5-\sqrt{5}.
30-16\sqrt{5}+2\left(\sqrt{5}\right)^{2}
Combine -6\sqrt{5} and -10\sqrt{5} to get -16\sqrt{5}.
30-16\sqrt{5}+2\times 5
The square of \sqrt{5} is 5.
30-16\sqrt{5}+10
Multiply 2 and 5 to get 10.
40-16\sqrt{5}
Add 30 and 10 to get 40.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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