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Question
Evaluate:
`(cot^2 41^circ)/(tan^2 49^circ) - 2 sin^2 75^circ/cos^2 15^circ`
Solution
`(cot^2 41^circ)/(tan^2 49^circ) - 2 sin^2 75^circ/cos^2 15^circ`
= `[cot(90^circ - 49^circ)]^2/(tan^2 49^circ) - 2 [sin(90^circ - 15^circ)]^2/cos^2 15^circ`
= `tan^2 49^circ/(tan^2 49^circ) - 2 cos^2 15^circ/cos^2 15^circ`
= 1 – 2
= – 1
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