Question

For f (x ) = x^3-9x^2, use calculus to determine the location of:
a. Any maximum or minimum points (tell which are max and which are min)

b. Any inflection points

Answer 1

y=x^3-9x^2 become x^2*(x-9)

so y=0 at x=0 & x=9

slope=dy/dx=3x^2-18x  or 3(x^2-6x)  or 3x*(x-6), so slope=0 at x=0 & x=6

inflex point...d2y=6x-18 or 6(x-3)...=0 at x=3