# Prove that the result of differentiating arc tan (1-x^2) + arc cot (1-x^2) is 0.

We have to prove that the derivative of arc tan (1-x^2) + arc cot (1-x^2) is 0.

We know that the derivative of arc tan x = 1/[1 + (1-x^2)^2] and the derivative of arc cot x = -1 / [1 + (1-x^2)^2]

Let f(x) = arc tan (1-x^2)...

We have to prove that the derivative of arc tan (1-x^2) + arc cot (1-x^2) is 0.

We know that the derivative of arc tan x = 1/[1 + (1-x^2)^2] and the derivative of arc cot x = -1 / [1 + (1-x^2)^2]

Let f(x) = arc tan (1-x^2) + arc cot (1-x^2)

f'(x) = -2x * 1/[1 + (1-x^2)^2] + (-2x)* -1/[1 + (1-x^2)^2]

=> -2x/[1 + (1-x^2)^2] + -(-2x)/[1 + (1-x^2)^2]

=> -2x/[1 + (1-x^2)^2] + 2x/[1 + (1-x^2)^2]

=> 0

The derivative of arc tan (1-x^2) + arc cot (1-x^2) = 0.

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