A plane progressive wave is represented by the equation y=cos(2πt−πx). The equation of wave with double of the amplitude and double the frequency but travelling in the opposite direction is ( )
A、y=2cos(4πt+πx)
B、y=2cos(5πt-πx)
C、y=2cos(4πt-πx)
D、y=2cos(3πt-πx)
发布时间：2025-07-13 19:29:30
