1. Find exact value of
2. find the area enclosed between the curve y = cos2x, the x-axis and the lines x = -pi/6 and x = +pi/6
4. find the equation of the tangent to the curve y = sin3x at the point (pi/4, 1/sqroot2)
5. Use the trapezoidal rule with 4 subintervals to find an approximation to the volume of the solid formed by rotating the curve y= sqroot cosx about the x-axis from x = 0 to x =pi/2.