Absolute value functions.

I've been really struggling with absolute value functions for a while now I'm hoping to get some help so that I can finally understand them.

How would you go about solving this absolute value inequality? I'll show my attempt to solve them and then hopefully you can tell me where I am going wrong.

$\left | 2x-1 \right |≤ \left | 3x \right |$

So next I would find the different cases.

$2x-1<0 $ or $x<\frac{1}{2} $ case 1
$2x-1≥0$ or $x≥\frac{1}{2} $  case 2

and then solve

$2x-1≤3x$  = $-1≤x$
or
$2x-1≤3x=-x≤1=x≤-1$ 

My first problem arises here I'm not sure which way I am supposed to solve it, because one way I get x ≤-1 and another way I get -1≤x. What am I doing wrong here? The next problem arises which case do I check to make sure both conditions are right for instance do I do


$x<\frac{1}{2} $ and $x≤-1$         or          $x≥\frac{1}{2} $ and $x≤-1$
Because in the first case, both conditions are met but in the second case both conditions are not met.

Now if I try and solve case two I have the same problems.

$2x-1≥-3x = 5x≥1 = x ≥\frac{1}{5} $
or
$2x-1≥-3x=-1≥-5x=\frac{1}{5} ≥x$ 

Now again I have the same problem where I have two values for x and again which case do a check to see if both conditions are met. This is the problem I am struggling with and I am not sure what I am doing wrong.


Answer

Answers can be viewed only if
  1. The questioner was satisfied and accepted the answer, or
  2. The answer was disputed, but the judge evaluated it as 100% correct.
View the answer

1 Attachment

Kav10 Kav10
1.7K
  • I understand the logic behind the first way of solving it, but the second way I'm a little unsure when it comes to the intervals I believe they're called. since the bounty was only $10 I don't expect you to do an in-depth explanation of them but if I open up another question on the website and set the bounty to $20 will you be able to answer my further questions? What time will you be online? I really like your way of explaining and I don't want someone else taking the bounty.

    • Kav10 Kav10
      +1

      OK, in a couple of hours when I get home, I should be able to provide more explanation on selecting the intervals. You can pay me here, by adding $20 or more tip. Sound good?

  • Kav10 Kav10
    0

    Added detailed steps. With these steps, you should hopefully be all set. When tipping, please remember 20% is taken by the website. Thanks.

The answer is accepted.
Join Matchmaticians Affiliate Marketing Program to earn up to 50% commission on every question your affiliated users ask or answer.