sin51°+cos81°=cos21°
Answers
Answered by
3
=>sin 51° + cos 81° = cos 21°
=>cos 21° – cos 81° = sin 51°
=> L.H.S = cos 21° – cos 81°
= -2 Sin(21+81)/2×Sin(21-81)/2
= -2 Sin(102/2) × Sin(-30)
= 2 sin51° Sin30
=2 sin51° ×1/2
= Sin51° =RHS
=>cos 21° – cos 81° = sin 51°
=> L.H.S = cos 21° – cos 81°
= -2 Sin(21+81)/2×Sin(21-81)/2
= -2 Sin(102/2) × Sin(-30)
= 2 sin51° Sin30
=2 sin51° ×1/2
= Sin51° =RHS
abhi9934:
Thank u
okkkk
Similar questions