Question

Is identity sec2 a-tan2 a=1 is true for 0°

Answer 1

Yes , this identity is valid for 0°
sec^2 0 - tan^2 0
= 1 - 0 = 1

Answer 2

Step-by-step explanation:

sec^2a-tan^2a=1

is not only true for 0°it is true for all the values (0°,30°,45°,60°,90°)

Example:- if a=30then,

sec^2 30 - tan ^2 30 = 1

(2/√3)^2-(1/√3)^2 = 1

4/3-1/3= 1

4-1/3 = 1

3/3= 1

1=1

Hence proved

Hope it helps you