Project a) What is the inside function? What is its derivative? b) Perform the integration using u-substitution. 2. Which functions are solutions to the differential equation 3/" y = 0? Choose all that apply and justify your answers. a) y = ex b) y = sin(x) c) y = cos(3x) d) y = W 3. Determine the value, k, so that y = k cos(3x) + 4511100 is a solution to the differential equation y" + y = 9 cos(2x). .Annnn. - I - nun