v 4.18

\frac{E_{t 0}^{⊥}}{E_{i 0}^{⊥}} = \frac{2 \sin γ \cos α}{\sin (α + γ)}

${\frac{E_{t0}^\perp}{E_{i0}^\perp} = \frac{2 \sin \gamma \cos \alpha}{\sin( \alpha + \gamma)}}$

Error