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x  e µ(x–t)
               45.                y(t) dt = f(x),  0 < λ <1.
                      a [ln(x/t)] λ
                     Solution:                               x
                                              sin(πλ)  µx  d      f(t) dt
                                        y(x)=       e                      .
                                                               µt
                                                π      dx  a  te [ln(x/t)] 1–λ

                 1.7-3. Kernels Containing Exponential and Trigonometric Functions
                       x

               46.      e µ(x–t)  cos[λ(x – t)]y(t) dt = f(x).
                      a
                                                     x

                     Solution: y(x)= f (x) – µf(x)+ λ 2  e µ(x–t) f(t) dt.
                                    x
                                                    a
                       x


               47.      e µ(x–t)   A 1 cos[λ 1 (x – t)] + A 2 cos[λ 2 (x – t)] y(t) dt = f(x).
                      a
                     The substitution w(x)= e –µx y(x) leads to an equation of the form 1.5.8:
                                   x
                                                                            –µx
                                     A 1 cos[λ 1 (x – t)] + A 2 cos[λ 2 (x – t)] w(t) dt = e  f(x).
                                 a
                       x

                                 2
               48.      e µ(x–t)  cos [λ(x – t)]y(t) dt = f(x).
                      a
                     The substitution w(x)= e –µx y(x) leads to an equation of the form 1.5.9.
                        Solution:
                                 2λ 2     x  µ(x–t)                   √

                     y(x)= ϕ(x)+        e     sin[k(x – t)]ϕ(t) dt,  k = λ 2,  ϕ(x)= f (x) – µf(x).
                                                                                   x
                                  k   a
                       x

                                 3
               49.      e µ(x–t)  cos [λ(x – t)]y(t) dt = f(x).
                      a
                     The substitution w(x)= e –µx y(x) leads to an equation of the form 1.5.15:
                                             x
                                                3
                                              cos [λ(x – t)]w(t) dt = e –µx f(x).
                                            a
                       x

                                 4
               50.      e µ(x–t)  cos [λ(x – t)]y(t) dt = f(x).
                      a
                     The substitution w(x)= e –µx y(x) leads to an equation of the form 1.5.19:
                                            x

                                                4
                                              cos [λ(x – t)]w(t) dt = e –µx f(x).
                                            a
                         x                    n
               51.      e µ(x–t)   cos(λx) – cos(λt)    y(t) dt = f(x),  n =1, 2, ...
                      a
                     The right-hand side of the equation is assumed to satisfy the conditions f(a)= f (a)= ··· =

                                                                                     x
                     f (n) (a)=0.
                      x
                        Solution:
                                  (–1) n  µx        1    d    n+1               –µx
                            y(x)=      e  sin(λx)             F µ (x),  F µ (x)= e  f(x).
                                    n
                                  λ n!            sin(λx) dx


                 © 1998 by CRC Press LLC









                © 1998 by CRC Press LLC
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