Okay so my teacher has been away and hasent explained anything to us and we have to find

the

intercepts,
critical points,
intervals of increase and decrease,
points of inflection,
intervals of concavity,
local maximum or minimum points

for each of the following functions

Can you please help me?
1.g(x) = x^3 − 6x^2 + 9x
2.p(x) = x^4 − 4x^3

So far i have the first derivative of each
3x^2-12x+9
4x^3-12x^2

set the first derivative to zero, and solve. Those are the maxima/minima

then, find the value of the function at those maxima/minima.
Now, find the zeroes. set the function=0, solve for the zeroes.

Now, find the second derivative, solve when it is zero, that is the inflection point (find the value of the function there).