ABSTRACT
This occurs when the signs of two consecutive values of f (x) are different, that is,
f x f xi i( ) ( )+ <1 0
The sign change usually indicates that a real root has been passed. However, it may also indicate a discontinuity in the function. (e.g., tan x is discontinuous at x = π/2.)
Once the intervals in which the roots lie have been established, we can use several different methods for obtaining the real roots, as described in the following sections.
