sin(α)+sin(γ) = n2+n1$$sin(\alpha)+sin(\gamma)$$ = $$n2+n1$$

sin(α) = n2+n1-sin(γ)$$sin(\alpha)$$ = $$n2+n1-sin(\gamma)$$

α = arcsin((n2+n1-sin(γ)))$$\alpha$$ = $$arcsin((n2+n1-sin(\gamma)))$$

α = arcsin(n2+n1-sin(γ))$$\alpha$$ = $$arcsin(n2+n1-sin(\gamma))$$
