You have to specify a domain... Let's say from x = 0 to the intersection of the two curves (The curves are even and also intersect at the negative value, so the area would be 2x as much). There are 3 intersections to the right of zero, so you really need x bounds to this problem.
A) The limits of the integral are 0 to where the values for the functions are equal. Solve numerically: (x*, y*) = (2.521, -4.881) You can plot the two curves on a TI or on desmos and trace the point of intersection. You can double the area or integrate from x=-x* to x=x*
B) A = integral from 0 to x* of (ytrig-yquad) dx because the trig function is greater in this range. Substitute the y(x) into the integral.
C) Do the integral which is not very challenging, so I'll leave it to you. You can double it at this point if you choose to go from -x* to x*.
