SOLUTION: Can you find the exact value: 3cos(-pi/6) + cot(tan-1 square root 3)

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Question 881003: Can you find the exact value: 3cos(-pi/6) + cot(tan-1 square root 3)
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The exact values of the trigonometric functions of %220%22 , pi%2F6 , pi%2F4 , pi%2F3 , and pi%2F2 are well known.

cos%28pi%2F6%29=sqrt%283%29%2F2
tan%28pi%2F3%29=sqrt%283%29
In this problem, tan%5E%28-1%29%28sqrt%283%29%29 means the inverse tangent function, the angle whose tangent is sqrt%283%29 ,
which happens to be pi%2F3,
but the cotangent of any angle is the reciprocal of the tangent (if they both exist), so we know that
cot%28tan%5E%28-1%29%28sqrt%283%29%29%29=1%2Fsqrt%283%29=sqrt%283%29%2F3 ,
just as we also knew that cot%28pi%2F3%29=sqrt%283%29%2F3
Putting it all together,