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प्रश्न
The value of 2sinθ can be `a + 1/a`, where a is a positive number, and a ≠ 1.
विकल्प
True
False
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उत्तर
This statement is False.
Explanation:
Let a = 2, then `a + 1/a = 2 + 1/2 = 5/2`
If 2sinθ = `a + 1/a`, then a
2sinθ = `5/2`
⇒ sinθ = `5/4` = 1.25
Which is not possible ...[∵ sin θ ≤ 1]
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संबंधित प्रश्न
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Prove the following identities:
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If `sec theta + tan theta = p,` prove that
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Activity:
L.H.S. = `square`
= `square/(sinθ) + (sinθ)/(cosθ)`
= `(cos^2θ + sin^2θ)/square`
= `1/(sinθ.cosθ)` ...`[cos^2θ + sin^2θ = square]`
= `1/(sinθ) xx 1/square`
= `square`
= R.H.S.
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