# FWHM of a gaussian function

by peterjaybee
Tags: function, fwhm, gaussian
 P: 62 Hi, I have a gaussian of the form $$exp[-\frac{\pi*x^{2}}{A^2}]$$. I know that the FWHM=0.939A, but I cannot prove it. I Let $$exp[-\frac{\pi*x^{2}}{A^2}=0.5$$ (i.e. the half maximum part) taking natural logs I get rid of the exponential, but then which bit represents the full width?