Capacitor Output Response to Nonsinusoidal Source

I'm a little bit confuse about the output waveform of the capacitor. What I mean is, in the capacitor, we can use the formula Vo = Vs(1-e^-t/RC) for charging and Vo = Vse^-t-t1/RC) for discharging but I notice that these use DC sources where Vo is the instantaneous voltage. I figured out that sinusoidal input can be solve to find the Vo but how about sawtooth, triangular or square wave ? how can I find Vo ?