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Question
Prove that `(cos(90^circ - A))/(sin A) = (sin(90^circ - A))/(cos A)`.
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Solution
L.H.S. = `(cos(90^circ - A))/(sin A)`
= `(sin A)/(sin A)`
= 1
R.H.S. = `(sin(90^circ - A))/(cos A)`
= `(cos A)/(cos A)`
= 1
∴ L.H.S. = R.H.S.
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