Signal Processing using MATLAB

Currently i am working on Signal Processing using MATLAB and I have few queries.

1. If I have a biharmonic sinusoidal curve (asinw1t+bsinw2t), how can I sample out the datas from this signal in a a 1D-array? 2. Using the 1D-array datas (x(t) vs t) how can I perform the FFT and the IFFT to get the required curves frequency domain and time domain?

please some one help me with the codes to understand this problem.