In: Math
d2xdt2+k2x=F0eωt
With the following initial conditions x0=0 and x'0=0. (Assume k≠ω)
please note that here in question equation is given in x(t) and solution ask in y(t) which is not possible so I correct the given NHDE and intial conditions in y(t). If you have any doubt in this question then please tell me in comment otherwise like my solution.