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Question
sec4 A − sec2 A is equal to
Options
tan2 A − tan4 A
tan4 A − tan2 A
tan4 A + tan2 A
tan2 A + tan4 A
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Solution
The given expression is .`sec^4 A-sec^2A`
Taking common `sec^2 A` from both the terms, we have
`Sec^4 A-sec^2 A`
= `sec^2 A (sec^2 A-1)`
= `(1+tan^2 A)tan^2 A`
=`tan^2 A+tan^4 A`
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Activity:
L.H.S = `square`
= `square (1 - (sin^2theta)/(tan^2theta))`
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