Is This Expression Correct for U Differing from 0.5 by More Than 0.25?

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The discussion focuses on the correct algebraic expression for the condition that a number U, within the unit interval, differs from 0.5 by more than 0.25. The initial expression presented, 0.5 - U > 0.25, is partially correct but lacks the necessary consideration of the unit interval. The more accurate expression is |0.5 - U| > 0.25, with the additional constraint that 0 ≤ U ≤ 1. Participants clarify that the unit interval is defined as [0, 1]. The conversation emphasizes the importance of including the interval condition in the expression.
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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
 
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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.
 
symbolipoint said:
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.
Unit interval.

Should that be 0 ≤ U ≤ 1 ?
 
SammyS said:
Unit interval.

Should that be 0 ≤ U ≤ 1 ?

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