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Question
If θ is an acute angle of a right angled triangle, then which of the following equation is not true?
Options
sin θ cot θ = cos θ
cos θ tan θ = sin θ
cosec2 θ – cot2 θ = 1
tan2 θ – sec2 θ = 1
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Solution
tan2 θ – sec2 θ = 1
Explanation:
tan2 θ – sec2 θ = 1 is not true
∵ sec2 θ = 1 + tan2 θ
or sec2 θ – tan2 θ = 1
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