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Question
Choose the correct alternative:
Which is not correct formula?
Options
1 + tan2θ = sec2θ
1 + sec2θ = tan2θ
cosec2θ − cot2θ = 1
sin2θ + cos2θ = 1
Solution
1 + sec2θ = tan2θ
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RELATED QUESTIONS
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Activity: L.H.S. = cotθ + tanθ
= `cosθ/sinθ + square/cosθ`
= `(square + sin^2theta)/(sinθ xx cosθ)`
= `1/(sinθ xx cosθ)` ....... ∵ `square`
= `1/sinθ xx 1/cosθ`
= `square xx secθ`
∴ L.H.S. = R.H.S.
