ssthakur1@sheffield.ac.uk

I am trying to find the maximum and minimum peaks of a function which goes as: y=x1 cos(f1+ teta) + x2 cos(2*f1); The peak values are straightforward for cases where the frequencies are equal or when they are non-multiples. I am having trouble to quantify the maximum and minimum values of 'y'. Note: teta, x1 and x2 all these vary from time to time. I am therefore looking for a generalised expression (accuracy <5%). Thanks in advance.