Absolute Values and Inequality understanding

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jzapata87
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Homework Statement



I saw this in my real analysis textbook and I have been trying to understand how this equation [tex]\left | x-c \right |< 1[/tex]

you can get this:[tex]\left | x \right |\leq \left | c \right | + 1[/tex]

Homework Equations



I wanted to know what steps made this possible , particularly why it changed from [tex]< to \leq[/tex]

The Attempt at a Solution


My thinking was that, they did this because it makes no difference as to if you put [tex]< or \leq[/tex]

Any help is appreciated!
Thanks
 
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[tex]|x|-|c|\leq |x-c| < 1 \Rightarrow |x|-|c| \leq 1[/tex]
This one is true because of the symbol [tex]\Rightarrow[/tex] (or as you said, it makes no difference). Things would be different if it were [tex]\Leftrightarrow[/tex].
 
hikaru1221 said:
[tex]|x|-|c|\leq |x-c| < 1 \Rightarrow |x|-|c| \leq 1[/tex]
This one is true because of the symbol [tex]\Rightarrow[/tex] (or as you said, it makes no difference). Things would be different if it were [tex]\Leftrightarrow[/tex].

You forgot to tell the young man that to understand this problem he also needs to understand two of the three basic norms Homogeneity and Subadditivity