If sin 3θ = cos(20° – θ), then θ is equal to?
Show answer & explanation
Correct answer: C
Explanation
Correct Answer is option 3 i.e. 35
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Concept |
Understanding |
Application |
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Sin(90 –θ) = cos θ
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Given sin 3θ = cos(20° – θ) |
sin 3θ = cos(20° – θ) Use the formula: ⇒ sin 3θ = sin[90°– (20°–θ)] ⇒ 3θ = 90°– 20° + θ ⇒ 2θ = 70° ⇒θ = 35° |