Question

When light passing through one transparent medium reaches the surface of another Transparent medium changes its trajectory to achieve the minimum time path. This trend is known as Snell's Law.   Sen(a) /v1 =Sen(b)/v2  where a and b are the figure angles and v1 and v2 the speeds of light in each medium, respectively. Using Lagrange multipliers to deduce that law by imposing the restriction x+y=a.

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Answer 1