Mark (√) against the correct answer in the following:

If ?


Given that


or


Since tan2x=sec2x-1, therefore




Hence, or


Let x=tanθ


θ=tan-1x


Hence,


Using , we get



Using -tan x = tan(-x), we get



=-2θ


=-2 tan-1 x


Differentiating with respect to x, we get


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