If \(\frac{(1 +sinθ-cosθ)}{(1 +sinθ +cosθ)} + \frac{(1 + sinθ +cosθ)}{(1 + sinθ-cosθ)}\)= 4, then which of the following values will be suitable for θ ?
If \(\frac{(1 +sinθ-cosθ)}{(1 +sinθ +cosθ)} + \frac{(1 + sinθ +cosθ)}{(1 + sinθ-cosθ)}\)= 4, then which of the following values will be suitable for θ ? Correct Answer 30°
Given:
+ = 4
Formula:
sin 30° = 1/2
Calculation:
+ = 4
⇒ / = 4
⇒ (1 + sin2 θ + cos2 θ + 2 sin θ - 2 sin θ cos θ - 2 cos θ + 1 + sin2 θ + cos2 θ + 2 sin θ + 2 sin θ cos θ + 2 cos θ)/ = 4
⇒ (1 + 1 + 4 sin θ + 1 + 1)/(1 + sin2 θ + 2 sin θ - cos2 θ) = 4
⇒ (4 + 4 sin θ)/ = 4
⇒ /(1 + sin2 θ + 2 sin θ - 1 + sin2 θ) = 4
⇒ /(2 sin2 θ + 2sin θ) = 4
⇒ / = 4
⇒ 2/sin θ = 4
⇒ sin θ = 2/4
⇒ sin θ = 1/2
⇒ sin θ = sin 30°
∴ θ = 30°
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Feb 20, 2025