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प्रश्न
If cosA + cos2A = 1, then sin2A + sin4A = 1.
पर्याय
True
False
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उत्तर
This statement is True.
Explanation:
∵ cosA + cos2A = 1
⇒ cosA = 1 – cos2A = sin2A ...[∵ sin2A + cos2A = 1]
⇒ cos2A = sin4A
⇒ 1 – sin2A = sin4A ...[∵ cos2A = 1 – sin2A]
⇒ sin2A + sin4A = 1
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संबंधित प्रश्न
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1 + cot2θ = ?
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Activity:
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= `cos^2theta xx square .....[1 + tan^2theta = square]`
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= 12
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