Evaluate
-4\sqrt{11}-12\approx -25.266499161
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\frac{8\left(3+\sqrt{11}\right)}{\left(3-\sqrt{11}\right)\left(3+\sqrt{11}\right)}
Rationalize the denominator of \frac{8}{3-\sqrt{11}} by multiplying numerator and denominator by 3+\sqrt{11}.
\frac{8\left(3+\sqrt{11}\right)}{3^{2}-\left(\sqrt{11}\right)^{2}}
Consider \left(3-\sqrt{11}\right)\left(3+\sqrt{11}\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{8\left(3+\sqrt{11}\right)}{9-11}
Square 3. Square \sqrt{11}.
\frac{8\left(3+\sqrt{11}\right)}{-2}
Subtract 11 from 9 to get -2.
-4\left(3+\sqrt{11}\right)
Divide 8\left(3+\sqrt{11}\right) by -2 to get -4\left(3+\sqrt{11}\right).
-12-4\sqrt{11}
Use the distributive property to multiply -4 by 3+\sqrt{11}.
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