 The variable is formula_202 and the polynomial can be represented by formula_203.Thus formula_204 is the required 1-D frequency response in terms of Chebyshev polynomial formula_203.If we consider formula_206 to be a transformation function whereformula_206 maps to formula_202,then we get,

formula_209

The contours and the symmetry of formula_210 depend on that of formula_211.