maths

(1) What are the following values? sin(π/3), cos(2π/3), tan(5π/4), sin(5π/3), cos(9π/4), tan(3π/2)

 (2) Explain why sin^2(x) + cos^2(x) = 1 for any x. 

 (3) What are the domain and range of sin(x), cos(x) and tan(x)?  

(4) What are the inverse functions of the following? f(x) = (2x-3)/(-x+2), f(x) = (4x-1)^3 + 2  

(5) What are the following values? 16^(3/4), 9^(-3/2)