Math Integration
posted by Anonymous .
Integrate:
f (x)/(2x + 1) dx
let f represent integrate sign
let u = x, du = dx => dx = du
= f (u)/(2u + 1) du
= f u (2u + 1)^(1) du
= (1/2)u^2 (ln2u + 1) + c
= (1/2)x^2 (ln2x + 1) + c
...what did I do wrong? The correct answer is
(1/2)x  (1/4)ln2x + 1 + c
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