Formulating an expression

1. Sep 28, 2011

magnifik

I'm having trouble trying to decipher this:

A number U is on the unit interval. Write the algebraic expression for
"U differs from 0.5 by more than 0.25"

This is what I did...am I doing this correctly?
0.5-U > 0.25
after doing the algebra
U < 0.25

2. Sep 28, 2011

symbolipoint

You have most of the right thinking on this. Better might be include the condition that it's on this unit interval.

|0.5-U| > 0.25 AND -1<=U<=1, that is, if this unit interval is one unit from both sides of zero. You can work with that and come to you needed expression for U.

3. Sep 28, 2011

SammyS

Staff Emeritus
Unit interval.

Should that be 0 ≤ U ≤ 1 ?

4. Sep 28, 2011

magnifik

Yes, I was under the impression that the unit interval is [0,1]