Question

If tan A = cot A, find the value of cos 2A, where 0º < A < 90°​

Answer 1

Answer:

cos 2A = 0

Step-by-step explanation:

As 0° < A < 90°

tan A = cot A is at only one condition when A = 45°

So, cos 2A = cos 2*45°

cos 90° = 0

Answer 2

Hey mate! Here is your answer

=> tan A = cot A

=> tan A = tan (90 - A)

=> A = 90 - A

=> 2A = 90°

=> A = 90°/2 = 45°

Then

=> cos 2A

=> cos 2 × 45 = 90°

=> cos 90° = 0

Answer: 0

I hope this answer will help you ^-^