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Question
sec4A(1 - sin4A) - 2tan2A = 1
Solution
डावी बाजू = sec4A(1 - sin4A) - 2tan2A
= sec4A[12 – (sin2A)2] – 2tan2A
= sec4A .(1 – sin2A) (1 + sin2A) – 2tan2A
= sec4A cos2A (1 + sin2A) – 2tan2A ...`[(∵ sin^2θ + cos^2θ = 1), (∴ 1 - sin^2θ = cos^2θ)]`
= `1/cos^4A . cos^2A(1 + sin^2A) - 2tan^2A`
= `1/cos^2A (1 + sin^2A) - 2tan^2A`
= `1/cos^2A + sin^2A/cos^2A - 2tan^2A`
= sec2A + tan2A – 2tan2A
= sec2A – tan2A
= 1 ................[∵ sec2θ – tan2θ = 1]
= उजवी बाजू
∴ sec4A(1 - sin4A) - 2tan2A = 1
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RELATED QUESTIONS
sec4θ - cos4θ = 1 - 2cos2θ
sinθ × cosecθ = किती?
sec θ(1 - sin θ) (sec θ + tan θ) = 1
`(sin θ - cos θ + 1)/(sin θ + cos θ - 1) = 1/(sec θ - tan θ)`
sec2θ − cos2θ = tan2θ + sin2θ हे सिद्ध करा.
`costheta/(1 + sintheta) = (1 - sintheta)/(costheta)` हे सिद्ध करा.
sin4A – cos4A = 1 – 2cos2A हे सिद्ध करण्यासाठी खालील कृती पूर्ण करा.
कृती: डावी बाजू = `square`
= (sin2A + cos2A) `(square)`
= `1 (square)` .....`[sin^2"A" + square = 1]`
= `square` – cos2A .....[sin2A = 1 – cos2A]
= `square`
= उजवी बाजू
जर sec θ = `41/40`, तर sin θ, cot θ, cosec θ च्या किमती काढा.
cot2θ – tan2θ = cosec2θ – sec2θ हे सिद्ध करा.
(sin A + cos A) (cosec A – sec A) = cosec A . sec A – 2 tan A हे सिद्ध करा.