Fairly simple but incorrect integral

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Homework Statement



\int\frac{dx}{1+\sqrt[3]{x-2}}

The answer is given: =\frac{3}{2}(x-2)^\frac{2}{3}-3(x-2)^\frac{1}{3}+ln|1+(x-2)^\frac{1}{3}|+C

Homework Equations





The Attempt at a Solution



\int\frac{dx}{1+\sqrt[3]{x-2}}

u=\sqrt[3]{x-2}

u^3=x-2

3udu=dx

=3\int\frac{udu}{1+u}

w=1+u

w-1=u

dw=du

=3\int\frac{w-1dw}{w}

=3\int\frac{wdw}{w}-3\int\frac{dw}{w}

=3\int dw-3\int\frac{dw}{w}

=3w-3ln|w|+C

=3(1+u)-3ln|1+u|+C

=3(1+\sqrt[3]{x-2})-3ln|1+\sqrt[3]{x-2}|+C

=3+3(x-2)^\frac{1}{3}-3ln|1+(x-2)^\frac{1}{3}|+C
 
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Your equation for dx is wrong. If u3 = x -2, then 3u2du = dx.
 
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