The equation R = [(n1-n2)/(n1+n2)] has been both theoretically derived and experimentally verified in relation to light refraction index and reflection. It can be mathematically derived from Fresnel's equations, which describe how light behaves at the interface between different media. The equation provided is a special case of the more general reflection coefficient formula, R = [(n1-n2)/(n1+n2)]². Resources were shared for further understanding of the derivation and applications of these equations. This discussion clarifies the foundational principles behind the light refraction index and its reflection properties.