Analytic continuation is a way of extending the domain over which a complex function is defined.
Analytic continuation (sometimes called simply "continuation") provides a way of extending the domain over which a complex function is defined. The most common application is to a complex analytic function determined near a point z_0 by a power series f(z) = sum_(k = 0)^∞ a_k (z - z_0)^k.
graduate school level