Question

(Prove that):
sin 80° - cos 110° = root 3 sin 50°​

Answer 1

Step-by-step explanation:

sin 80° = sin (50 + 30)°

= sin 50° cos 30° + sin 30° cos 50°

= sin 50 √3 /2 + cos 50°/2

cos 110° = cos (50 + 60)°

= cos 50° cos 60° - sin 50° sin 60°

= cos 50° / 2 - sin 50° √3/2

sin 80° - cos 110°

= sin 50° √3/2 + cos 50° /2 - cos 50°/2 + sin 50° √3/2

= √3 sin 50°