Trigonometry
Determine the exact value of the expression without using a calculator.
cos(tan−1(−5))\cos\left(\tan^{-1}\left(-5\right)\right)cos(tan−1(−5))
2626\frac{\sqrt{26}}{26}2626
−52626-\frac{5\sqrt{26}}{26}−26526
526\frac{5}{26}265
5626\frac{5\sqrt6}{26}2656