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x


               98.      sin[λ(x – t)] cos[λ(x + t)]y(t) dt = f(x),  f(a)= f (a)=0.
                                                                       x
                      a
                     Using the trigonometric formula

                               sin(α – β) cos(α + β)=  1    sin(2α) – sin(2β) ,  α = λx,  β = λt,
                                                  2
                     we reduce the original equation to an equation of the form 1.5.37:

                                            x

                                             sin(2λx) – sin(2λt) y(t) dt =2f(x).
                                          a
                                       1 d     f (x)

                                               x
                        Solution: y(x)=              .
                                       λ dx cos(2λx)
                       x

               99.      cos[λ(x – t)] sin[λ(x + t)]y(t) dt = f(x).
                      a
                     Using the trigonometric formula


                               cos(α – β) sin(α + β)=  1    sin(2α) + sin(2β) ,  α = λx,  β = λt,
                                                  2
                     we reduce the original equation to an equation of the form 1.5.38 with A = B =1:

                                           x


                                             sin(2λx) + sin(2λt) y(t) dt =2f(x).
                                          a
                        Solution with sin(2λx)>0:

                                                d      1       x  f (t) dt
                                                                  t
                                         y(x)=     √            √         .
                                               dx    sin(2λx)  a  sin(2λt)
                         x

               100.      A cos(λx) sin(µt)+ B cos(βx) sin(γt) y(t) dt = f(x).
                      a
                     This is a special case of equation 1.9.15 with g 1 (x)= A cos(λx), h 1 (t) = sin(µt), g 2 (x)=
                     B cos(βx), and h 2 (t) = sin(γt).

                       x


               101.      A sin(λx) cos(µt)+ B sin(βx) cos(γt) y(t) dt = f(x).
                      a
                     This is a special case of equation 1.9.15 with g 1 (x)= A sin(λx), h 1 (t) = cos(µt), g 2 (x)=
                     B sin(βx), and h 2 (t) = cos(γt).
                       x


               102.      A cos(λx) cos(µt)+ B sin(βx) sin(γt) y(t) dt = f(x).
                      a
                     This is a special case of equation 1.9.15 with g 1 (x)= A cos(λx), h 1 (t) = cos(µt), g 2 (x)=
                     B sin(βx), and h 2 (t) = sin(γt).
                         x
                             β           γ
               103.      A cos (λx)+ B sin (µt) y(t) dt = f(x).
                      a
                                                                                    γ
                                                                  β
                     This is a special case of equation 1.9.6 with g(x)= A cos (λx) and h(t)= B sin (µt).


                 © 1998 by CRC Press LLC









                © 1998 by CRC Press LLC
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