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Question
What is the value of (1 − cos2 θ) cosec2 θ?
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Solution
We have,
`(1-cos^2 θ) cosec ^2 θ=sin^2θ xx cosec^2 θ`
=` sin^2θ xx(1/sin θ)^2`
= `sin^2 θ xx1/( sin^2θ)`
`= 1`
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Solution :
L.H.S. = cotθ + tanθ
= `cosθ/sinθ + sinθ/cosθ`
= `(square + square)/(sinθ xx cosθ)`
= `1/(sinθ xx cosθ)` ............... `square`
= `1/sinθ xx 1/square`
= cosecθ × secθ
L.H.S. = R.H.S
∴ cotθ + tanθ = cosecθ × secθ
