How it works ?
The INTERMEDIATE VALUE THEOREM states:
If g is a CONTINUOUS FUNCTION over [a,b], and if N = any output between g(a) and g(b), where g(a) and g(b) are not equal, then there exists an input c in the open interval (a,b) so that g(c) = N.
This applet dynamically illustrates this fact.
Just make sure the function you enter is CONTINUOUS over [a,b]!
Note: You can simply drag points A and B to the left and right to adjust the values of a and b.
You can also simply enter in any N value between g(a) and g(b) by moving the BIG BLUE POINT or simply by entering in a value.