Question

prove that cos square 45 degree + theta + cos square 45 degree minus theta sin 60 + theta into cos 30 minus theta is equals to 1

Answer 1

cos² 45° +∅ + cos² 45° - ∅sin 60° + ∅ × cos 30° - ∅ = 1

cos² 45° + cos² 45° - ∅sin 60° + ∅cos 30° + ∅ - ∅ = 1

2 (cos² 45°) + - ∅cos ( 90-60 ) + ∅cos 30° = 1

2 (cos² 45°) + - ∅cos 30° + ∅cos 30° = 1

2 (cos² 45°) = 1

2 ( 1 / √2 ) ² = 1

2 ( 1 / 2 ) = 1

2/2 = 1

1=1

LHS= RHS

∴ Hence Proved