Posted by james on .
For all x in the interval [11,13] the function f is defined by x^3(x+3)^4
On which two intervals is the function increasing?
Find the region in which the function is positive

CALCULUs 
drwls,
Evaluate the derivative of f. The function is increasing where the derivative >0. It increases for x between 11 and 3 and between 0 and +13
The points where f(x) = 0 are x=0 and x=3. At x>0, it is positive.