Is My Calculation Correct for O.4^(|x-2|/|x+2|) = 0.4^2?

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Homework Help Overview

The discussion revolves around the inequality O.4^(|x-2|/|x+2|) < 0.4^2, focusing on the implications of the absolute values and the behavior of the function across different intervals of x. Participants are exploring the conditions under which the inequality holds true, while considering restrictions such as x ≠ -2.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are breaking down the inequality into cases based on the intervals defined by the critical points -2 and 2. They discuss the behavior of the absolute values and how to handle the inequalities when multiplying or dividing by negative quantities. Some express uncertainty about the correctness of their intervals and the implications of their calculations.

Discussion Status

There is an ongoing exploration of different approaches to solving the inequality, with participants questioning their own reasoning and the correctness of their intervals. Some have offered guidance on how to handle the absolute values and the implications of the function's behavior, while others are still clarifying their understanding of the problem.

Contextual Notes

Participants note the restriction that x cannot equal -2, and there is a recognition of the need to consider different cases based on the intervals created by the critical points. There is also mention of the potential for confusion when switching inequality signs during calculations.

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O.4^(|x-2|/|x+2|) = 0.4^2 Help Me :(

O.4^(|x-2|/|x+2|) < 0.4^2

so (|x-2|/|x+2|) < 2

restrictions: x≠-2

so for:

|x-2|------> (x-2) when x ≥ 2
-------> -(x-2) when x<2

|x+2| -------> (x+2) when x≥ -2
----------> -(x+2) when x<-2
with this i now have three separate intervals for calculation

(1)X< -2 (2)-2<x<2 (3)x>2

where-2, and 2 are holes

so for the ineterval x<-2

-(x-2)/-(x+2) < 2

negatives cancel multipy by (x+2) on both sides

x-2 < 2(x+2)
x - 2 < 2x+4
x> -6
this fits within its domain.
--------------------------------------------------------------------------------
for interval -2<x<2

(x-2)/(x+2) < 2

-x+2 < 2x +4
-2 < 3x
x> -2/3

this fits within its domain
-----------------------------------------------------------------
interval X>2

(x-2)/(x+2) < 2
x-2 < 2x + 4
x>-6can some one tell me if my intervals are correct?
wow i can't believe i spent my time on this stupid problem all day, just because in my scond interval. i forgot to switch the inequality sign in divisoninteval 2 -2<x<2

-(x-2)< 2(x+2)
-x + 2 < 2x +4
-2< 3x
DIVIDE siwtch sign :'"""""""(

x < -2/3there for since x> -6 for interval x<-2
and x< -2/3 for -2<x<2

xE(-6, -2)U(-2, -2/3)
 
Last edited:
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Plutonium88 said:
O.4^(|x-2|/|x+2|) < 0.4^2

so (|x-2|/|x+2|) < 2

restrictions: x≠-2

ax is a decreasing functions if 0<a<1; so 0.4f(x) is decreasing, therefore, (|x-2|/|x+2|)>2;
 


Actually what I said is wrong di dividing does not change inequalityNmy answer is wrong please hel
 


(|x-2|/|x+2|) < 2 → |x-2| < 2|x+2|

I think the easiest way to solve this would be by breaking |x| < y into the two cases x < y and x > -y for positive y, then apply that again since the original inequality has to absolute values. This will ultimately give you four cases to work out, and each of the two solutions will be repeated.
 


Plutonium88 said:
so for the ineterval x<-2

-(x-2)/-(x+2) < 2

negatives cancel multipy by (x+2) on both sides

x-2 < 2(x+2)
x - 2 < 2x+4
x> -6
this fits within its domain.
--------------------------------------------------------------------------------
x<-2 ,implies x+2<0
so when multiplying by x+2 ,inequality sign will change.
 


pcm said:
x<-2 ,implies x+2<0
so when multiplying by x+2 ,inequality sign will change.

ty for trying to help, i just got it on friday.what you have to do is solve the inequality like this for the three different intervals.
0.4^|x-2|/|x+2| < 0.4^2
|x-2|/|x+2| > 2
|x-2|/|x+2| > 2

|x-2|/|x+2| - 2 > 0
(|x-2|-2|x+2|)/|x+2| > 0then when you solve like this, you can do interval charts for each of the domains/intervals and find your answers. ty for the help tho. A friend at school helped me solve it, so respects to him also.
 
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