Hi!

Complete the square for $\displaystyle \frac12x^2-x+3$

$\displaystyle \frac{-2}{2(1)}\,=\,1$

$\displaystyle \frac12(x^2 - 2x + 1 - 1) + 3$

$\displaystyle \frac12(x-1)^2 - 2$

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- Apr 27th 2013, 10:38 PMUnrealCompleting the square with fraction as coefficient of x^2
Hi!

Complete the square for $\displaystyle \frac12x^2-x+3$

$\displaystyle \frac{-2}{2(1)}\,=\,1$

$\displaystyle \frac12(x^2 - 2x + 1 - 1) + 3$

$\displaystyle \frac12(x-1)^2 - 2$ - Apr 27th 2013, 10:50 PMProve ItRe: Completing the square with fraction as coefficient of x^2
You make life difficult on yourself if you skip steps. The first thing to do is to take out $\displaystyle \displaystyle \begin{align*} \frac{1}{2} \end{align*}$ as a factor, then complete the square on everything left over, then multiply that factor back through.

- Apr 27th 2013, 11:27 PMUnrealRe: Completing the square with fraction as coefficient of x^2
$\displaystyle \frac{-2}{2(1)}\,=\,1$

$\displaystyle \frac12(x^2 - 2x) + 3$

$\displaystyle \frac12\left[(x^2 - 2x + 1 - 1) + 3\right]$

$\displaystyle \frac12(x-1)^2 - 1 + 3$

$\displaystyle \frac12(x-1)^2 + 2$ - Apr 27th 2013, 11:51 PMProve ItRe: Completing the square with fraction as coefficient of x^2
I'm not giving any more help until you learn to follow the instructions you've been given.

- Apr 28th 2013, 12:14 AMUnrealRe: Completing the square with fraction as coefficient of x^2
My solution is what I understand from the instructions given.

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Originally Posted by**Prove It**

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Originally Posted by**Prove It**

$\displaystyle \frac12\left[(x-1)^2 + 5\right]$

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Originally Posted by**Prove It**

- Apr 28th 2013, 12:26 AMProve ItRe: Completing the square with fraction as coefficient of x^2
And this is correct. Well done.