InterviewSolution
Saved Bookmarks
| 1. |
Find the value of 1 – 2 sin2θ + sin4θ.1). sin4θ2). cos4θ3). cosec4θ4). sec4θ |
|
Answer» We KNOW that, ⇒ sin2θ = 1 – cos2θ Squaring on both sides (? (a + B)2 = a2 + 2ab + b2) ⇒ sin4θ = 1 + cos4θ – 2cos2θ Now, 1 – 2 sin2θ + sin4θ (? cos 2x = 2cos2x – 1 = 1 – 2sin2x) = 2cos2θ – 1 + 1 + cos4θ – 2cos2θ = cos4θ ∴ 1 – 2 sin2θ + sin4θ = cos4θ |
|