Evaluate: `intx/((x^2+4)sqrt(x^2+9))dx`

Explanation

Let `u=sqrt(x^2+9)`

`dusqrt(x^2+9)=xdx`



Thus equation becomes,

`int(dusqrt(x^2+9))/((u^2-5)(sqrt(x^2+9)))`


`=int(du)/(u^2+9)`

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