Contains 13 historical, archaic, and unusual functions. They are: Versine (VERS(X); 1 – cos x), Coversine (COVERS(X); 1 – sin x), Haversine (HAV(X); sin(x/2)^2), Normalized Sampling (NSINC(X); sin(π * x)/(π * x)), Exsecant (EXSEC(X); sec x - 1), Gundermannian (GD(X); atan(sinh x)), Inverse Gundermannian (INVGD(X); asinh(tan x)), Dilogarithm (DILN(X); ∫ (ln t / (t – 1) dt, 1, x)), Exponential Polynomial (EPOLY(N, X); Σ(x^j / j!, j, 0, n)), Hypotenuse of a Right Triangle (HYPER(A,B); √(a^2 + b^2)), Langevin Function (LANGEVIN(X); 1/tanh x – 1/x), General Mean Function (GENMEAN(N,A,B), N = 1, arithmetic mean, N = 2, root mean square, N = -1, harmonic mean, (a^n + b^n) / 2)^(1/n)), and Logarithmic Integral (Li(X); Ei(LN(x))). |