Page 749 - Handbook Of Integral Equations
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Supplement 6


               Tables of Fourier Cosine Transforms





               6.1. General Formulas

                                                                              ∞
                                                                      ˇ
                 No       Original function, f(x)     Cosine transform, f c (u)=  f(x) cos(ux) dx
                                                                            0
                                                      ˇ
                                                              ˇ
                  1   af 1 (x)+ bf 2 (x)             af 1c (u)+ bf 2c (u)
                                                     1
                                                          u
                                                       ˇ
                  2   f(ax),  a >0                    f c
                                                     a    a
                                                          d 2n
                       2n
                                                              ˇ
                  3   x f(x),  n =1, 2, ...          (–1) n   f c (u)
                                                         du 2n
                                                          d 2n+1               ∞
                                                                      ˇ
                                                        n
                                                                ˇ
                  4   x 2n+1 f(ax),  n =0, 1, ...    (–1)   2n+1  f s (u), f s (u)=  f(x) sin(xu) dx
                                                         du                  0
                                                      1       u + b        u – b
                                                         ˇ
                                                                    ˇ
                  5   f(ax) cos(bx),  a, b >0           f c       + f c
                                                     2a      a          a
               6.2. Expressions With Power-Law Functions
                                                                              ∞
                                                                      ˇ
                 No       Original function, f(x)     Cosine transform, f c (u)=  f(x) cos(ux) dx
                                                                            0
                       1if 0 < x < a,                1

                  1                                    sin(au)
                       0if a < x                     u
                       x     if 0 < x <1,

                                                     4         2  u
                  2    2 – x if 1 < x <2,               cos u sin
                                                     u 2        2
                       0     if 2 < x
                       1
                  3       ,  a >0                    – sin(au) si(au) – cos(au) Ci(au)
                      a + x
                                                     π  –au
                        1                              e     (the integral is understood
                  4         ,  a >0                  2a
                       2
                      a + x 2                        in the sense of Cauchy principal value)
                        1                            π sin(au)
                  5         ,  a >0
                      a – x 2                           2u
                       2
                          a            a               –au
                  6    2       2  +  2      2        πe   cos(bu)
                      a +(b + x)   a +(b – x)
                         b + x        b – x            –au
                  7              +                   πe   sin(bu)
                       2
                                    2
                      a +(b + x) 2  a +(b – x) 2
                        1                            1  –3      au       π  au
                  8         ,  a >0                  2  πa exp – √  sin   + √
                       4
                      a + x 4                                    2      4    2
                 © 1998 by CRC Press LLC

               © 1998 by CRC Press LLC
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