Cos2 20 +cos2 70+ sin 48 sec42+cos 40 cosec 50 - Maths - Introduction to Trigonometry

Question

Cos2 20 +cos2 70+ sin 48 sec42+cos 40 cosec 50

Bakul Biswas · Accepted Answer

Dear Student,
cos220 + cos270 + sin 48 
 sec 42 + cos 40 
 cosec 50=cos290-70 + cos270 + sin 48 
 sec90-48 + cos 40 
 cosec90-40=sin270 + cos270 + sin 48 
 cosec 48 + cos 40 
 sec 40=sin270 + cos270 + sin 48 × 1sin 48 + cos 40 × 1cos 40=1 + 1 + 1=3
Hope this information will clear your
doubts about topic

If you have any more doubts just ask here on the forum and our
experts will try to help you out as soon as
possible
Regards