Question

If f'(x)=(x-3)(x+1)(x+2), which of the following statements about f(x) is not true?
A)f(x) is concave up on (1,2)
b) f(x) is a 4th degree polynomial
c)f(x) has a horizontal tangent line at x=3
d) f(x) has a relative minimum at x=-2
e) f(x) is increasing on (-2,-1)