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Question
Four alternative answers for the following question are given. Choose the correct alternative and write its alphabet:
sin θ × cosec θ = ______
Options
1
0
`1/2`
`sqrt2`
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Solution
sin θ × cosec θ = 1
Explanation:
sin θ × cosec θ
= `sintheta xx 1/sinθ ... [cosec theta = 1/(sintheta)]`
= 1
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Activity:
L.H.S. = `square`
= `square (1 - (sin^2θ)/(tan^2θ))`
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