Page 753 - Handbook Of Integral Equations
P. 753

∞

                                                                      ˇ
                 No       Original function, f(x)     Cosine transform, f c (u)=  f(x) cos(ux) dx
                                                                            0
                       1      √       √                 π      ab        a + b 2  π
                                                                      2
                  9   √ sin a x sin b x , a, b >0        sin     sin       –
                        x                              u     2u        4u    4

                                                       π        u 2       u 2
                           2
                 10   sin ax ,  a >0                       cos     – sin
                                                       8a      4a       4a
                                                         √
                                                          π           Au 2           Bu 2
                            2       2                           exp –        sin ϕ–         ,
                                                       2
                                                                      2
                                                                                     2
                                                           2 1/4
                 11   exp –ax  sin bx ,  a >0        (A +B )         A +B 2         A +B 2
                                                     A =4a, B =4b, ϕ =  1  arctan(b/a)
                                                                       2
                      1 – cos(ax)                    1       2
                 12            ,  a >0                 ln 1 –  a

                          x                          2      u 2

                      1 – cos(ax)                      1 π(a – u)if u < a,
                 13            ,  a >0                 2
                         x 2                          0         if u > a
                 14   x ν–1  cos(ax),  a >0, 0 < ν <1  1  Γ(ν) cos    1  πν    |u – a| –ν  +(u + a) –ν
                                                     2        2
                                                        1  –1 –ab
                      cos(ax)                          2 πb e  cosh(bu)if u < a,
                 15         ,  a, b >0                 1  –1 –bu
                       2
                      x + b 2                           πb e   cosh(ab)  if u > a
                                                       2
                                                     b      1            1
                 16   e –bx  cos(ax),  a, b >0               2   2  +     2  2
                                                     2 (a + u) + b  (a – u) + b
                       1      √                         π      a 2  π
                 17   √ cos a x                          sin    +
                        x                              u     4u   4
                       1      √        √                π      ab       a + b 2  π
                                                                      2
                 18   √ cos a x cos b x                  cos     sin        +
                        x                              u     2u        4u     4
                                                                 2
                                                     1    π     a + u 2       au
                            2
                 19   exp –bx  cos(ax),  b >0              exp –        cosh
                                                     2   b        4b         2b

                           2                           π       1 –1 2       1 –1 2
                 20   cos ax ,  a >0                       cos  a u  + sin  a u
                                                       8a     4           4
                                                         √
                                                          π           Au 2           Bu 2
                            2       2                           exp –        cos ϕ–         ,
                                                                                      2
                                                       2
                                                           2 1/4
                                                                      2
                 21   exp –ax  cos bx ,  a >0        (A +B )         A +B 2         A +B  2
                                                     A =4a, B =4b, ϕ =  1  arctan(b/a)
                                                                       2
               6.7. Expressions With Special Functions
                                                                              ∞
                                                                      ˇ
                 No       Original function, f(x)     Cosine transform, f c (u)=  f(x) cos(ux) dx
                                                                            0
                                                      1
                                                              u
                  1   Ei(–ax)                        –  arctan
                                                      u       a
                                                      0     if 0 < u < a,

                  2   Ci(ax)                            π
                                                      –     if a < u
                                                        2u
                                                       1
                  3   si(ax)                         –   ln    u + a    ,  u ≠ a
                                                      2u   u – a
                 © 1998 by CRC Press LLC


               © 1998 by CRC Press LLC
                                                                                                             Page 737
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