silemus.

29Integral of 2x/(x2+1)2x/(x^2 + 1)

Evaluate ∫012xx2+1 dx\displaystyle \int_0^1 \frac{2x}{x^2 + 1}\,dx. Give the answer to 3 decimal places.

Substitute u = x²+1, so du = 2x dx, turning the integral into ∫₁² (1/u) du = ln u from 1 to 2 = ln 2 ≈ 0.693.

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