Cosec²72° - tan²18°=1

Asked by abhishekmonupatel27 | 23rd Feb, 2021, 04:31: PM

Expert Answer:

To prove: cosec²72° - tan²18°=1
L.H.S = cosec²72° - tan²18°
         = cosec(90°- 18°)² - tan²18°
         = sec²18° - tan²18°
         = 1
         = R.H.S
Hence, proved.

Answered by Yasmeen Khan | 23rd Feb, 2021, 06:51: PM