Answer:
Verified
Step-by-step explanation:
Use [tex]\tan{x}=\frac{\sin{x}}{\cos{x}}[/tex] , [tex]\sin^2{x}+\cos^2{x}=1[/tex] and [tex]\sec{x}=\frac{1}{\cos{x}}[/tex]
LHS=[tex]\tan^2{x}+1=\frac{\sin^2{x}}{\cos^2{x}} + 1=\frac{\sin^2{x}+\cos^2{x}}{\cos^2{x}}=\frac{1}{\cos^2{x}}=\sec^2{x}[/tex]=RHS
