How to represent this absolute value inequality with constants?

In summary, the conversation is about representing a formula in an x-graph where the constant "a" is not conditioned. The question is whether the graph needs to be separated into different cases for the value of "a." The answer is that only one interval, (a - delta, a + delta), needs to be shown and the point x = 0 is not important. Another question is asked about how to represent x = 0 not being included in the graph, and the suggestion is to use round brackets for the end points.
  • #1
kenny1999
235
4
Homework Statement
absolute value
Relevant Equations
inequality
see attached image, it asks to repesent it in x-graph
constant "a" isn't conditioned.
Do I need to separate it into a few cases of the constant a and represent each in one x-graph?
Screenshot 2021-03-09 140649.png
 
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  • #2
What do you mean by an x-graph? Do you mean on the x-axis?
 
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  • #3
You should read that the formula means x is around a within distance ##\epsilon##.
 
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  • #4
PeroK said:
What do you mean by an x-graph? Do you mean on the x-axis?

yes. Sorry I am not in English language
 
  • #5
anuttarasammyak said:
You should read that the formula means x is around a within distance ##\epsilon##.

a isn't conditioned, e.g. >0 or <0

so do I need to separate into a few cases and draw the graph??
 
  • #6
OK . This is what I have done, I don't know if I am correct. I am teaching my cousin, but I have left school for 20 years
12231231313131.jpg
 
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  • #7
Another question , I avoid starting a new topic. Am I correct??
66.jpg
 
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  • #8
kenny1999 said:
OK . This is what I have done, I don't know if I am correct. I am teaching my cousin, but I have left school for 20 years
I think all you need to do is show one interval ##(a - \delta, a + \delta)##. You don't need all those different cases. The point ##x = 0## is not important here.
 
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  • #9
kenny1999 said:
Another question , I avoid starting a new topic. Am I correct??
I guess that's ##0 < |x - a| < \delta##?
 
  • #10
To make your diagram more clear, show ##a## on it. Then show ##a-\delta## and ##a+\delta##. There is no reason to even show where anything else, like ##x=0##, is. Then one diagram takes care of all the cases.
 
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  • #11
PeroK said:
I think all you need to do is show one interval ##(a - \delta, a + \delta)##. You don't need all those different cases. The point ##x = 0## is not important here.

Hi, did you mean I do not have to consider the possible ranges of value of a ? (Since a isn't conditioned but the delta is given that >0, that's why I am wondering if I need to separate a into different ranges of value
 
  • #12
PeroK said:
I guess that's ##0 < |x - a| < \delta##?
No, "Another question" is really another, not related to the first question, yes the first question was ##0 < |x - a| < \delta##

I think the second question does NOT include x=0. How to draw a symbol to represent that x=0 isn't included?? an arrow??
 
  • #13
kenny1999 said:
Hi, did you mean I do not have to consider the possible ranges of value of a ? (Since a isn't conditioned but the delta is given that >0, that's why I am wondering if I need to separate a into different ranges of value
You don't have to consider different values for ##a##.
 
  • #14
kenny1999 said:
No, "Another question" is really another, not related to the first question, yes the first question was ##0 < |x - a| < \delta##

I think the second question does NOT include x=0. How to draw a symbol to represent that x=0 isn't included?? an arrow??
It's ##x =a## that is excluded. I would just use ##(a-\delta, a)(a, a + \delta)## with round brackets to show the end points are excluded.
 

FAQ: How to represent this absolute value inequality with constants?

What is an absolute value inequality?

An absolute value inequality is an inequality that involves the absolute value of a variable, which is the distance of the variable from 0 on a number line. It can be represented as |x| < a or |x| > a, where a is a constant.

How do I represent an absolute value inequality with constants?

To represent an absolute value inequality with constants, you can use the symbols < and > to indicate less than or greater than, respectively. The absolute value of the variable should be placed between these symbols, and the constant should be placed outside the absolute value symbol. For example, |x| < 5 or |x| > 2.

What is the difference between < and > when representing an absolute value inequality?

The symbol < represents "less than", while the symbol > represents "greater than". In terms of absolute value inequalities, < is used when the inequality is less than a certain value, and > is used when the inequality is greater than a certain value.

Can an absolute value inequality have more than one constant?

Yes, an absolute value inequality can have more than one constant. For example, |x| < 3 or |x| > 2 and |x| < 5 are both valid absolute value inequalities with multiple constants.

How do I solve an absolute value inequality with constants?

To solve an absolute value inequality with constants, you can use the properties of absolute value to isolate the variable. If the inequality is |x| < a, the solution set will be all values of x that are within a distance of a from 0 on the number line. If the inequality is |x| > a, the solution set will be all values of x that are outside a distance of a from 0 on the number line.

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