*Problem:*

Explore the sum *f + g* of the functions
**f(x) = x**^{3} - 4x
and
**g(x) = 2 cos(x)**

*Visualization:*

The following LiveMath Notebook evaluates the sum *f + g* and plots the
graphs of *f*, *g*, and *f + g*. You can modify the functions
*f* and *g* and see the resulting changes.
View an animation to see how this can be
done.
Which are the graphs of *f*,
*g*, and the sum *f + g*?
Answer

For which *x* is the brown graph
higher than the red graph?
Answer