a function is decreasing if the first derivative is negative.
It also helps to know what the graph looks like
http://www.wolframalpha.com/input/?i=plot+y+%3D+x%5E2%2F(x-3)%5E2
Where does the critical value of x = 6 come from?
Find the intervals on which x^2/(x-3)^2 is decreasing.
a. (0,6)
b. (0,3), (3,6)
c. (-inf,0), (6,inf)
The critical numbers are x=0 and 6, but since there is an asymptote at x=3, I'm not sure whether a or b is the answer.
2 answers
I'm sorry...the function is supposed to be x^2/(x-3).