1. (8 points) Prove that f: f: f(t)dtdu = f: f(u)(:v u)du. Hint: Differentiate both sides with respect to :L'. 2. (6 points) Prove that 3. (10 points) Find the length of the curve y2($1)2, ,1<:c give exact answer. points a solid is form by revolving the region bounded between curves y and a: about line find volume of region. solve differential equation f ln cot e r particular solution to d eqmy d3: _ satisfying>