# Re: Expansion

1. Mar 20, 2006

### Schrodinger's Dog

I have the equation 1/2(x-3)^2-18

Now normally I have no trouble with expansion of brackets but for some reason this is puzling to me.

1/2x^2-3x-9-18

I get 1/2x^2-3x-27

I checked the answer with a maths package and it comes up with : -

1/2x^2-3x-27/2 Why? What am I missing here. where does the 27/2 come in?

I also get 1/2(x-3)(x-9) if I factorise it again? My pacckage obviously likes, multiple different factorisations.

Anyway I'm a bit stumped, normally I don't have a problem with this sort of straightforward stuff but I'm stumped on this one?

2. Mar 20, 2006