If `._(i)mu_(j)` represents refractive index when a light ray goes from mefium `i` to medium `j`,
Channel: Doubtnut
Date: 2021-11-08

If `._(i)mu_(j)` represents refractive index when a light ray goes from mefium `i` to medium `j`, then the product `._(2)mu_(1)xx._(3)mu_(2)xx._(4)mu_(3)` is equal to