I'm really struggling with this right now. i know how to solve for everything but c and i can't find any help anywhere :( i just need help with finding c but feel free to explain the entire thing for others

g is a trigonometric function of the for g(x)=acos(bx+c)+d

below is the graph of g(x). the function has a maximum point at (2,11) and a minimum point at (3.5,1).

find a formula for g(x). give an exact expression.