Hey all,

I just had few questions that couldn't wait until I see my teacher to clear up. Hopefully someone won't mind explaining...

1. I've never encountered the symbol "|", as in (x | 2) . What does it mean, and how would I go about deciding it's use?

2. What role does 'K' play in the equation f(x) = k(x - s)(x - t)(x - u)etc.?

I know that if k is negative, we reflect the graph in the x-axis, but is it also (as I remember it) the term that will stretch the graph vertically?

3. An application question gives me a function $\displaystyle y = 26.55x^3 - 170.56x^2 + 249.62x + 1257.80$, 0 < x < 4 and asks me to state the restricted domain... I'm not sure if it *is* 0 < x < 4, or what. It's just a guess, and I need an explanation really.

Thanks to anyone who takes the time to give me hand yet again!

- Cam