The diagram shows part of the curve with equation y=f(x) , where f(x)=1+2sin(px°+q°) , p and q being positive constants and q ≤ 90. The curve cuts the y-axis at the point A and the x-axis at the points C and D. The point B is a maximum point on the curve.
Given that the coordinates of A and C are (0, 2) and (45, 0) respectively:
(a) Calculate the value of q.
(b) Show that p=4.
(c) Find the coordinates of B and D.
I can do question a, but I am really stuck on b and c.