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प्रश्न
Which of the following is true for all values of θ (0° ≤ θ ≤ 90°)?
पर्याय
cos2 θ – sin2 θ = 1
cosec2 θ – sec2 θ = 1
sec2 θ – tan2 θ = 1
cot2 θ – tan2 θ = 1
उत्तर
sec2 θ – tan2 θ = 1
Explanation:
∵ sec2 θ = 1 + tan2 θ
∴ sec2 θ – tan2 θ = 1
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