Interestingly enough, the trigonometric functions that define those relationships are also closely tied to circles. Needless to say, this makes trig one of the hardest topics in math for students ...

We show that the rational functions associated with the lemniscate functions and primary numbers of Gaussian integers, defined by Eisenstein, has a symmetrical relation with respect to the zeros and ...

We consider a method of estimating an unknown regression curve by regression on a combination of low-order polynomial terms and trigonometric terms. Estimation based on trigonometric functions alone ...