Question

Find the following figure , find the value of :

1. sin A
2. sec A
3. cos²A + sin²A​

Answer 1

Step-by-step explanation:

Given:- AB = a ---- B

BC = a ---- P

To prove:- 1. sin A

2. sec A

3. cos²A + sin²A

Proof:- By Phythagoras theorem,

AC² = AB² + BC²

AC² = a² + a²

AC² = 2a²

AC = 2a ---- H

1. Sin A = P

H

Sin A = a

2a

Sin A = 1

2

2. Sec A = H

B

Sec A = 2a

a

Sec A = 2

3. cos²A + sin²A = ( B )² + ( P )²

H H

= a² + a²

2a² 2a²

= a² + a²

4a² 4a²

= 2a²

8a²

= 1

4

Hope it helps you....