Write Snell's law in general mathematical terms.

Explanation

The general form of Snell.s law may be written as `n_(1)sin i_(1)=n_(2) sin i_(2)` where `i_(1)` - angle of incidence in a medium (1) and `i_(2)` - angle of refraction in a medium (2) for a pair of media (1) and (2), `n_(1)` - refractive index of medium (1) and `n_(2)` - refractive index of medium (2).