Question

ILLUD !
(v) sec 70° sin 20° + cos 20° cosec 70° = 2

Prove that!!!!!​

Answer 1

sec(90°-70°)= sin 20°

cosec(90°-70°)= cos 20°

ie.,= sin20°.sin20° + cos 20°.cos20°

=1+1

=2

hence proved