Two identical loudspeakers are located at points A & B, 2m apart. The loudspeakers are driven by the same amplifier (coherent and are in the same phase). A small detector is moved out from point B along a line perpendicular to the line connecting A & B. Taking speed of sound in air as 332 m/s, find the frequency below which there will be no position along the line BC at which destructive interference occurs.
The Attempt at a Solution
I am not sure how would I approach this problem. I started with calculating the path difference when the detector is at a distance x from its initial position,
For destructive interference,
where ##\lambda## is the wavelength of the wave.
I don't know how should I proceed from here.
Any help is appreciated. Thanks!