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Question
Find the value of `θ(0^circ < θ < 90^circ)` if :
`cos 63^circ sec(90^circ - θ) = 1`
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Solution
`cos63^circ sec(90^circ - θ) = 1`
`cos 63^circ cosecθ = 1`
⇒ `cos63^circ = sinθ`
⇒ `cos 63^circ = cos(90^circ - θ)`
⇒ `63^circ = 90^circ - θ`
⇒ `θ = 27^circ`
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Activity:
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