1. The problem statement, all variables and given/known data 2. Relevant equations 3. The attempt at a solution I know dV=1/C∫idt and that we integrate the voltage from V to V0. What I don't get are the boundary conditions for t - How do we get what we get in the parenthesis? My closest assumption is that the t/T values refer to the areas described by the voltage graph - triangles and rectangles. I have noticed that the we section the period every time there's a change in current, and therefore, in voltage (0<t<2T, 2T<t<3T, etc.) Also what use am I supposed to make of Q=-IT? From this equation and the first one we get i=dQ/dt, but so what?