function fx = p22_fun ( n, x ) %*****************************************************************************80 % %% P22_FUN evaluates the integrand for problem 22. % % Interval: % % 0 <= X <= 1 % % Integrand: % % 1 / ( X^4 + X^2 + 1 ) % % Exact integral: % % ln ( 9 ) / 8 + pi / sqrt ( 48 ) % % Approximate Integral (20 digits): % % 0.72810291322558188550... % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 03 November 2009 % % Author: % % John Burkardt % % Reference: % % Philip Davis, Philip Rabinowitz, % Methods of Numerical Integration, % Second Edition, % Dover, 2007, % ISBN: 0486453391, % LC: QA299.3.D28. % % Parameters: % % Input, integer N, the number of evaluation points. % % Input, real X(N), the evaluation points. % % Output, real FX(N), the integrand values. % fx = 1.0 ./ ( x.^4 + x.^2 + 1.0 ); return end