Answer
$f(x)=(x+1)^2-1$
See graph
Work Step by Step
We are given the function:
$f(x)=x^2+2x$
Complete the square:
$f(x)=x^2+2x+1-1=(x+1)^2-1$
We start graphing with the basic function $a(x)=x^2$.
We horizontally shift $a(x)$ by one unit to the left to get $b(x)=(x+1)^2$.
Then we vertically shift $b(x)$ one unit downward to get $f(x)=(x+1)^2-1$.
We use 3 points: $(-1,-1),(0,0),(1,3)$