If y=Asin(ωt−kx), then the value of dydx is
Which of the following two wave equations can form stationary wave?
(i) Y=Asin(ωt−kx)
(ii) Y=Acos(ωt−kx)
(iii) Y=Asin(ωt+kx)
(iv) Y=Acos(ωt+kx)