 . The problem is to determine the coefficients c
 . The problem is to determine the coefficients c from integral transforms of
 from integral transforms of  and
 and  over a finite interval [
 over a finite interval [  ]. The main objective is to present a device which obtains the c
 ]. The main objective is to present a device which obtains the c linear equations, whereas the straightforward approach leads to a system involving twice as many equations.
 linear equations, whereas the straightforward approach leads to a system involving twice as many equations.