Wave Optics — Physics STD 12 Science — Question

For constructive interference, the path difference should be even multiple of \(\frac{\lambda}{2}\) or phase difference should be 2πn. Where n = 0,1, 2....
For destructive interference, the path difference should be the odd multiple of \(\frac{\lambda}{2}\) or \((2 n-1) \frac{\lambda}{2}\) or phase difference should be the odd multiple of π i.e., (2n - 1)π