Answer:
20[tex] \tan 2\phi[/tex]
Step-by-step explanation:
20 sin 2∅ sec 2∅
= 20 [tex]\frac{\sin 2\phi}{\cos 2\phi}[/tex]
= 20[tex] \tan 2\phi[/tex] (answer)
since, we know that
sec(∅) = [tex]\frac{1}{\cos \phi}[/tex]
and [tex]\frac{\sin \phi}{\cos \phi}[/tex] = tan(∅)