There are two coherent sources `S_(1)` and `S_(2)` which produce waves in same phase placed on Y axis at points (0, 2d) and (0, d) as shown in figure-6.23. A detector D is placed at origin which moves along X direction, find the number of maxima recorded by detector excluding points x = 0 and `x = oo`. Given that wavelength of light produced is `6200Å` and separation between sources is 0.34 mm.