Two waves travelling in a medium in the x-direction are represented by `y_(1) = A sin (alpha t - beta x)` and `y_(2) = A cos (beta x + alpha t - (pi)/(4))`, where `y_(1)` and `y_(2)` are the displacements of the particles of the medium `t` is time and `alpha` and `beta` constants. The two have different :-

Options

A. Speeds
B. Directions of propagation
C. Wavelengths
D. Frequencies

Answer

B

Explanation

In the given equations of the two waves are travelling in opposite directions, rest all parameters are same.