1. The problem statement, all variables and given/known data Consider y_1=Asin(5x)exp(-2t) y_2=Aexp(4ix)exp(-2it) y_3=Asin(2x-5t)exp(-2t) (i)which one represents a wave that propagates at constant speed with no change in its profile (ii)Confirm it satifies the wave equation and obtain the wave velocity (iii)Comment qualitatively on the behaviour descried by the other 2 2. Relevant equations 3. The attempt at a solution (i) i think it's the second one. I took the Re(y) and got Acos(3x-2t) so the amplitude is constant, while the other 2 will decrease in amplitude as exp(-2t) will tend to 0? (ii)just differeniate it and stick into equation (iii)They will oscillate with the same frequency but the amplitude will decrease?