A separable differential equation is a first order
differential equation that can be written in the form
These can be solved by integration, by noting that
hence 
This latter equation defines  implicitly as a function of
 implicitly as a function of  , and
in some cases it is possible to explicitly solve for
, and
in some cases it is possible to explicitly solve for  as a function
of
 as a function
of  .
.
William Stein
2006-03-15