Compare the intesities of two points iocated at respective distance `(beta)/(4)` and `(beta)/(3)` from the central maxima in a interference of YDSE (`beta` is the fringe width)

Explanation

`Delta theta= (2pi)/(lambda) Delta x = (2pi)/(lambda) ((d)/(D)(beta)/(4))= (2pi)/(lambda) ((d)/(D)(lambdaD)/(4d))`
`:. Delta theta =(2pi)/(4)(pi)/(2)implies I =4I_(0)cos^(2)((pi)/(4))`
Similarly `Delta theta=(2pi)/(3) implies I= 4I_(0) cos^(2) ((2pi)/(2xx3))=I_(0)`
`:. "required ratio" = 2:1`