Let $$f(x)=x^4+4x^3+100$$ Find the global minimum value of the function $f$, that is, give the minimum value of $f$ and the value of $x$ for which this occurs.
This is not a homework problem. I have a exam and I don't know how to answer this question. I did the first and second derivative test. I don't need answer. I don't wanna fail my exam. Can anyone explain step by step how they would do these kind of problems. I am sorry if this is a lot to explain, but I looked on youtube and all of the videos explained with the intervals. It did not help. Thank you.