1. What's the exact value of cot[cot^-1 sqrt3/3]?

2. What's the exact value of sin^-1 (cos pi/2) ?

3. What's the exact value of tan (sin^-1 x/2) ?

So the problems ask to find and calculate the exact value of the trigonometric equation in the following equations and the best answers would be the following:

#1. sqrt (3) / 3

#2. Arcsine of zero is 0

#3. x/sqrt (4-x^2)

I hope you are satisfied with my answer and feel free to ask for more if you have questions and further clarifications. Have a nice day