Định nghĩa nào sau đây đúng về tích phân suy rộng?

\[\mathop \smallint \limits_{ - \infty }^{\rm{b}} {\rm{f(x)dx}} = \mathop {\lim }\limits_{{\rm{a}} \to - \infty } \mathop \smallint \limits_{\rm{a}}^{\rm{b}} {\rm{f(x)dx}}\]

\[\mathop \smallint \limits_{\rm{a}}^{ + \infty } {\rm{f(x)dx = }}\mathop {\lim }\limits_{{\rm{a}} \to + \infty } \mathop \smallint \limits_{\rm{a}}^{ - \infty } {\rm{f(x)dx}}\]

\[\mathop \smallint \limits_{ - \infty }^{\rm{b}} {\rm{f(x)dx}} = \mathop {\lim }\limits_{a \to 0 - } \mathop \smallint \limits_{{\rm{a + \varepsilon }}}^{\rm{b}} {\rm{f(x)dx}}\]

\[\mathop \smallint \limits_{\rm{a}}^{ + \infty } {\rm{f(x)dx}} = \mathop {\lim }\limits_{{\rm{\varepsilon }} \to 0} \mathop \smallint \limits_{\rm{a}}^{{\rm{b + \varepsilon }}} {\rm{f(x)dx}}\]