A is the amplitude, a the angular frequency of the first, b of the second cosine, d is a phase shift. The cosine was chosen so that a single oscillation can easily be made visible by setting a or b to zero. The dimension of the canvas is handy 15 × 7.5 units^{2}.

Just vary the parameters! Hint: Click on the parameter sliders or the number fields and control the change via your cursor keys. Have fun!

Export as SVG (for tiny computing: Stepsize = 1 oder bigger!)