These powers are called multiplicities.
Let's do another one:
Find the real zeros of
then draw a rough sketch of the graph:
What's the basic shape?
What are the real zeros?
We just need to do a little factoring...
real zeros: -2, 0 (kiss), 2
Why don't you check this guy on the graphing calculator?
Enter it as x^4-4x^2
(Your window may still be weird from the last guy we graphed... hit the RESET button on the calculator to fix it.)