# Homework Help: Trouble completing the square on the integral

1. Dec 6, 2011

### en bloc

1. The problem statement, all variables and given/known data

http://c811106.r6.cf2.rackcdn.com/se05h01043.png

2. Relevant equations

3. The attempt at a solution

When i complete the square i get; $\sqrt{}-x^2-4x+4 -4$

There's some algebra that i don't understand.

2. Dec 6, 2011

### SammyS

Staff Emeritus
First, complete the square for $x^2+4x\,.$ Then take the negative of the result.

3. Dec 7, 2011

### HallsofIvy

$-x^2- 4x= -(x^2+ 4x)$

Now complete the square for $x^2+ 4x$.