Differentiate log(1 + x2) with respect to tan–1x.
Let u = log(1 + x2) and v = tan–1x.
We need to differentiate u with respect to v that is find
.
On differentiating u with respect to x, we get
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We know![]()
[using chain rule]
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However,
and derivative of a constant is 0.
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Now, on differentiating v with respect to x, we get
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We know ![]()
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We have 

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Thus, ![]()