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|x-1| if x>1
how do you simplify this

User De Novo
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1 Answer

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Use the definition of absolute value.


|x| = \begin{cases} x &amp; \text{if } x \ge0 \\ -x &amp; \text{if } x < 0 \end{cases}

The absolute value is always non-negative. So if
x is already non-negative,
|x|=x is unchanged. But if
x is negative, then
|x|=-x because multiplying
x by -1 makes it positive.

Now, if
x>1, then by the definition of absolute value,


x > 1 \implies x - 1 > 0 \implies \boxedx - 1

User Atul Mishra
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