Respuesta :

Answer:

Integral doesn't converge

Step-by-step explanation:

In order to computed the improper integral replace infinite limit with a finite value:

[tex]\lim_k \to -\infty} (\int\limits^0_k {\frac{x}{x^2+3} } \, dx  )[/tex]

For the integrand [tex]\frac{x}{x^2+3}[/tex] substitute:

[tex]u=x^2+3\\du=2xdx[/tex]

[tex]\lim_k \to -\infty} (\frac{1}{2}  \int\limits^0_k {\frac{1}{u} } \, du  )[/tex]

The integral of 1/u is log(u):

Applying the fundamental theorem of calculus and substituing back for u=x^2 +3:

[tex]\lim_{k \to -\infty} (\frac{1}{2} log(x^2+3) \left \{ {{0} \atop {k}} \right )[/tex]

Evaluating the limits:

[tex]\lim_{k \to -\infty} (\frac{1}{2} log(x^2+3) \left \{ {{0} \atop {k}} \right ) =0.549-\infty= \infty[/tex]

Hence, the integral doesn't converge