Q4 (i)

cos A / 1- sinA

+

cos A / 1 + sinA

=2 sec A
(ii)

cos A / cosec A + 1

+

cos A / cosec A -1

=2 tan A
(iii)

(cos θ - sin θ)(1 + tan θ) / 2 cos²θ -1

= secθ

Solution

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