Some new uses of the image functions Original Research Article

We present a procedure and a MATHEMATICA code for the conversion of formulae expressed in terms of the trigonometric functions image, image or hyperbolic functions image, image to forms expressed in terms of image functions. The possibility of such a conversion is important in the evaluation of the coefficients of the approximation rules derived in the frame of the exponential fitting. The converted expressions allow, among others, a full elimination of the 0/0 undeterminacy, uniform accuracy in the computation of the coefficients, and an extended area of validity for the corresponding approximation formulae.