(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

I don;t think the actual problem I am trying to prove is relevant. But I have got to a step in my proof where I must show that | a - b | = | -(a - b)|

So by definition

|a - b| = +/- (a-b)

and |-(a - b)| = +/- (- (a - b)) = +/- (a-b)

Thus the two are equal.

Is this acceptable?

Or do I really need to break it down into cases where a - b is Positive negative or 0?

Thanks.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Question on a step in my proof.

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