12. Techniques of Integration

Evaluate the integral or state that it diverges. 

${\int }_{-\infty }^{-1}\frac{2}{x^3}dx$

Evaluate the integral or state that it diverges. 

${\int }_2^{\infty }\frac{1}{x(lnx{)}^4}dx$

Which of the following integrals is improper?

Which of the following integrals is improper because the interval of integration is infinite?