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प्रश्न
दाखवा की: `tanA/(1 + tan^2 A)^2 + cotA/(1 + cot^2A)^2` = sinA × cosA.
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उत्तर
डावी बाजू = `tanA/(1 + tan^2 A)^2 + cotA/(1 + cot^2A)^2`
= `tanA/(sec^2A)^2 + cotA/("cosec"^2A)^2` ...`[(∵ 1 + tan^2θ = sec^2θ","),(1 + cot^2θ = "cosec"^2θ)]`
= `tanA/(sec^4A) + cotA/("cosec"^4A)`
= `tanA xx 1/(sec^4A) + cotA xx 1/("cosec"^4A)`
= `sinA/cosA xx cos^4A + cosA/sinA xx sin^4A`
= sinA cos3A + cosA sin3A
= sinA cosA (cos2A + sin2A)
= sinA cosA (1) ...[∵ sin2θ + cos2θ = 1]
= sinA cosA
= उजवी बाजू
∴ `tanA/(1 + tan^2A)^2 + cotA/(1 + cot^2A)^2` = sinA cosA
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संबंधित प्रश्न
(sec θ - cos θ)(cot θ + tan θ) = tan θ sec θ
cot θ + tan θ = cosec θ sec θ
sec4θ - cos4θ = 1 - 2cos2θ
जर secθ = `13/12` , तर इतर त्रिकोणमितीय गुणोत्तरांच्या किमती काढा.
जर tan θ + cot θ = 2, तर tan2θ + cot2θ = ?
`(cos^2theta)/(sintheta) + sintheta` = cosec θ हे सिद्ध करा.
जर sec θ = `41/40`, तर sin θ, cot θ, cosec θ च्या किमती काढा.
`sqrt((1 + cos "A")/(1 - cos"A"))` = cosec A + cot A हे सिद्ध करा.
(1 – cos2A) . sec2B + tan2B (1 – sin2A) = sin2A + tan2B हे सिद्ध करा.
सिद्ध करा:
cotθ + tanθ = cosecθ × secθ
उकल:
डावी बाजू = cotθ + tanθ
= `cosθ/sinθ + sinθ/cosθ`
= `(square + square)/(sinθ xx cosθ)`
= `1/(sinθ xx cosθ)` ............... `square`
= `1/sinθ xx 1/square`
= cosecθ × secθ
= उजवी बाजू
∴ cotθ + tanθ = cosecθ × secθ
