Page 752 - Handbook Of Integral Equations
P. 752

∞
                                                                      ˇ
                 No       Original function, f(x)     Cosine transform, f c (u)=  f(x) cos(ux) dx
                                                                            0

                      ln x                           –  π   ln(4u)+ C +  π   ,
                  2   √                                 2u            2
                        x
                                                     C = 0.5772 ... is the Euler constant
                                                                          π     πν

                                                                 –ν
                                                             πν
                  3   x ν–1  ln x,  0 < ν <1         Γ(ν) cos   u   ψ(ν) –  tan     – ln u
                                                             2            2      2

                  4   ln    a + x    ,  a >0         2   cos(au) Si(au) – sin(au) Ci(au)
                        a – x                        u
                            2  2                     π     –au
                  5   ln 1+ a /x ,  a >0               1 – e
                                                     u
                         2
                        a + x 2                      π    –bu  –au
                  6   ln      ,  a, b >0               e   – e
                         2
                        b + x 2                      u
                                                           1
                                                                     2
                                                                 2
                                                      aC + a ln(u + a )+ u arctan(u/a)
                      –ax
                  7   e  ln x,  a >0                 –     2
                                                                   2
                                                                  u + a 2
                                                      a         π

                  8   ln 1+ e –ax   ,  a >0            2  –        –1
                                                     2u    2u sinh πa u
                                                      a    π
                            –ax                                     –1
                  9   ln 1 – e  ,  a >0                2  –  coth πa u
                                                     2u    2u
               6.6. Expressions With Trigonometric Functions
                                                                              ∞
                                                                      ˇ
                 No       Original function, f(x)     Cosine transform, f c (u)=  f(x) cos(ux) dx
                                                                            0
                                                       1
                                                      π   if u < a,
                      sin(ax)                          2
                  1         ,  a >0                    1  π  if u = a,
                        x                             4
                                                       0   if u > a
                                                       (u + a) –ν  – |u + a| –ν  sign(u – a)
                  2   x ν–1  sin(ax),  a >0, |ν| <1  π                  1
                                                           4Γ(1 – ν) cos  πν
                                                                       2
                                                        1  –ab
                      x sin(ax)                         πe   cosh(bu)  if u < a,
                  3           ,  a, b >0               2 1  –bu
                        2
                       x + b 2                        – πe    sinh(ab)if u > a
                                                        2
                                                        1  –2     –ab
                       sin(ax)                         2 πb  1 – e  cosh(bu)  if u < a,
                  4      2  2  ,  a, b >0              1  –2 –bu
                      x(x + b )                         πb e   sinh(ab)      if u > a
                                                       2
                                                     1     a + u       a – u
                  5   e –bx  sin(ax),  a, b >0                    +
                                                             2
                                                                          2
                                                     2 (a + u) + b 2  (a – u) + b 2
                      1   2                          1        2
                  6     sin (ax),  a >0                ln 1 – 4  a

                      x                              4       u 2

                      1    2                           1 π(2a – u)if u <2a,
                  7     sin (ax),  a >0                4
                      x 2                             0          if u >2a
                            a
                      1                              π    √
                  8     sin   ,  a >0                  J 0 2 au
                      x     x                        2
                 © 1998 by CRC Press LLC



               © 1998 by CRC Press LLC
                                                                                                             Page 736
   747   748   749   750   751   752   753   754   755   756   757