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Question
`(sec^2 theta-1) cot ^2 theta=1`
Solution
LHS = `(sec^2 theta -1 ) cot^2 theta`
=`tan^2theta xx cot^2 theta (∵ sec^2 theta - tan^2 theta =1)`
=`1/(cot^2theta) xx cot^2 theta`
=1
=RHS
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