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I tried converting to exponential, e^(1+x^2) -x -1 = 0 Then finding a contradiction but didn't find one. Then i differentiated to find a minima > 0. 2xe^(1+x^2) -1 = 0 but didn't find a solution as the term 2xe^(1+x^2) doesn't equal to 1 at any point x. Again even if there was any it still would have been a local minima.

Aditya Jha
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Let f(x) = 1 + x^2 - log(1 + x)

Conditional: x > -1

f'(x) = 2x -1/(1+x)

f'(x) = 0 => x = (sqrt(3) - 1) / 2

f"(x) = 2 + 1/(1+x)^2, always greater than 0

So f(sqrt(3) - 1) / 2) must be the minimum value of f

f(sqrt(3) - 1) / 2) is approximate 0.8

So f(x) always greater than 0.8

Therefore, f(x) = 0 has no solution.

Therefore log(1+x) and (1+x^2) do not intersect.