My teacher says whenever you are given a graph with oscillations try to picture a pendulum, which I guess works for the moment.
The thing that confuses me are the equations given on the equation sheet,
For example if a question asks for maximum displacement and you have a graph of Displacement vs Time, the max displacment would be the peak right? So what's up with the equation x=ACos(wt) when would you have to input cos(wt) to find the displacement? same goes for the other ones e.g. v=-AwSin(wt).
Also where do these equations come from:
Potential energy= 0.5*k*x^2
Kinetic Energy= 0.5*m*w^2*x^2