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Question
If `cosec theta = 2x and cot theta = 2/x ," find the value of" 2 ( x^2 - 1/ (x^2))`
Solution
2 `(x^2 - 1/(x^2))`
=`4/2(x^2 - 1/(x^2))`
=`1/2(4x^2 - 4/(x^2))`
=`1/2 [(2x)^2- (2/x)^2]`
=`1/2 [( cosec theta )^2 - (cot theta)^2]`
=`1/2 (cosec ^2 theta - cot^2 theta)`
=`1/2 (1)`
=`1/2`
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