Solving an Inequality: |x-3| < 2|x|

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Homework Statement



Solve the given inequality by interpreting it as a statement about distances in the real line:

|x-3| < 2|x|

Homework Equations





The Attempt at a Solution



I have no clue what to do here and I do not understand the answer in the textbook

Goes something like this.....
x^2 - 6x + 9.....Have no idea how they got that
= (x-3)^2
...and so forth
 
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There are two possibilities for x: either x is greater than or equal to 3, or x is less than 3.

If x ≥ 3, what does the inequality look like (i.e. without the absolute value)?
 
TheRedDevil18 said:

Homework Statement



Solve the given inequality by interpreting it as a statement about distances in the real line:

|x-3| < 2|x|

Homework Equations





The Attempt at a Solution



I have no clue what to do here and I do not understand the answer in the textbook

Goes something like this.....
x^2 - 6x + 9.....Have no idea how they got that
= (x-3)^2
...and so forth

They used ##|a|<|b| \leftrightarrow a^2<b^2##.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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