Determine the critical points of $f(x)=(x+2)^2$.

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Lesson Parent: 
Chapter 18 - Critical Points
Problem: 

Determine the critical points of $f(x)=(x+2)^2$.

Answer: 

$x=-2$

Solution: 

First find the derivative. Use the Chain Rule to find that $f\,'(x)=2(x+2)$.

Now set $f\,'(x)=0$ and do some algebra to find the value of $x$. Like so:
\begin{eqnarray}
f\,'(x)&=&0\\
2(x+2)&=&0\\
x+2&=&0\\
x&=&-2.
\end{eqnarray}
The function has only one critical point and it is at $x=-2$.