A index of certain type of glass has an an index of refraction of 1.66 for red light and 1.65 for violet light. If a beam of white in air approaches the glass with an angle of incidence of 49.0 degree, by what angle will the red light be separated from the violet light inside the glass?

Answer 1

For red, the sine of the refraction angle is
Sin49 /1.66
That comes from Snell's law, which you should know.
For violet, it is sin49/1.65
Compute the refraction angles using a sin^-1 function and take the difference.