Advertisements
Advertisements
Question
sec4A(1 - sin4A) - 2tan2A = 1
Advertisements
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
APPEARS IN
RELATED QUESTIONS
(sec θ - cos θ)(cot θ + tan θ) = tan θ sec θ
जर secθ = `13/12` , तर इतर त्रिकोणमितीय गुणोत्तरांच्या किमती काढा.
(sec θ + tan θ) (1 - sin θ) = cos θ
tan4θ + tan2θ = sec4θ - sec2θ
जर cos θ = `24/25`, तर sin θ = ?
जर tan θ + cot θ = 2, तर tan2θ + cot2θ = ?
cot2θ × sec2θ = cot2θ + 1 हे सिद्ध करा.
sec2θ − cos2θ = tan2θ + sin2θ हे सिद्ध करा.
cot θ + tan θ = cosec θ × sec θ, हे सिद्ध करण्यासाठी खालील कृती पूर्ण करा.
कृती:
डावी बाजू = `square`
= `square/sintheta + sintheta/costheta`
= `(cos^2theta + sin^2theta)/square`
= `1/(sintheta*costheta)` ......`[cos^2theta + sin^2theta = square]`
= `1/sintheta xx 1/square`
= `square`
= उजवी बाजू
`(1 + sin "B")/"cos B" + "cos B"/(1 + sin "B")` = 2 sec B हे सिद्ध करा.
