SOLUTION: how to prove x ≤ |x|

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Question 978838: how to prove x ≤ |x|
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
If x%3E=0 then abs%28x%29=x so then,
x%3C=x
x-x%3C=0
0%3C=0
True because 0=0.
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If x%3C0 then abs%28x%29=-x so then,
x%3C=-x
2x%3C=0
However since x%3C0, then 2x%3C0 so this statement is also true since
2x%3C0
So you've proved it when x%3E=0 and when x%3C0, so the statement holds for all x.