Plzzz help me with these questions

1. Show that sin' @+ cos' @= 1 for 3 . [ 3 Marks ] 2. For the function h() = acos (k(t - d)) + c, describe what a, k, d and c represent if the function models the height of a car on a Ferris wheel. [ 4 Marks ] 3. Describe the properties of the function y - 2tan xx - 2 -1 . State the range for the function, and state the values for which the function is undefined. [ 7 Marks ]