The 2 absolute equation equality? find the max and min of x?

The minimum value is x = 1/3.In summary, the maximum value of x is 1 and the minimum value is 1/3. The third case is self-contradictory and therefore ruled out. The correct answers are 1 and 1/3.
  • #1
Helly123
581
20

Homework Statement


15_Mat_B_-_1.6.png


Homework Equations

The Attempt at a Solution


2x - 1 >= 0
x >= 1/2

x - 2 >= 0
x >= 2

for x <1/2
then 2x - 1 and x - 2 are negative
solve : -(2x-1) - (x-2) = 2
-3x + 3 = 2
x = 1/3

for 1/2 <= x < 2
the (2x - 1) positive, (x-2) negative
solve : 2x -1 -x + 2 = 2
x = 1

for x>= 2
both 2x -1 and x -2 = positive
2x - 1 + x - 2 = 2
3x = 5
x = 5/3

is my answer right? then the max of x is 5/3? and the min is 1/3?
 
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  • #2
Helly123 said:

Homework Statement


View attachment 205815

Homework Equations

The Attempt at a Solution


2x - 1 >= 0
x >= 1/2

x - 2 >= 0
x >= 2

for x <1/2
then 2x - 1 and x - 2 are negative
solve : -(2x-1) - (x-2) = 2
-3x + 3 = 2
x = 1/3

for 1/2 <= x < 2
the (2x - 1) positive, (x-2) negative
solve : 2x -1 -x + 2 = 2
x = 1

for x>= 2
both 2x -1 and x -2 = positive
2x - 1 + x - 2 = 2
3x = 5
x = 5/3

is my answer right? then the max of x is 5/3? and the min is 1/3?
These are the values I get, as well.
 
  • #3
Mark44 said:
These are the values I get, as well.
so what's the max and min of x? because the key answer not 1/3 and 5/3. but 1/3 and 1
 
  • #4
Your third case is self-contradictory. On the assumption that x >= 2, you get x = 5/3, which is < 2. So this case is ruled out, and the answers are 1/3 and 1.
 
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Likes Helly123
  • #5
Helly123 said:
so what's the max and min of x? because the key answer not 1/3 and 5/3. but 1/3 and 1
mjc123 said:
Your third case is self-contradictory. On the assumption that x >= 2, you get x = 5/3, which is < 2. So this case is ruled out, and the answers are 1/3 and 1.
Yes, @mjc123 is correct. I wasn't careful enough in checking my solutions. The maximum value is x = 1.
 

Related to The 2 absolute equation equality? find the max and min of x?

1. How do you solve the 2 absolute equation equality?

To solve the 2 absolute equation equality, you need to isolate the absolute value expressions on either side of the equal sign and then set up two separate equations. One with the positive value and one with the negative value of the absolute expressions. Then solve for the variable in each equation and check for extraneous solutions.

2. Can you give an example of the 2 absolute equation equality?

One example of the 2 absolute equation equality is |x + 3| = |2x - 5|. In this equation, isolating the absolute value expressions would give us two separate equations: x + 3 = 2x - 5 and -(x + 3) = 2x - 5. Solving these equations would give us the solutions x = 4 and x = 2.

3. What is the meaning of "absolute value" in this equation?

The absolute value in this equation refers to the distance of a number from 0 on the number line. It is always a positive value, regardless of the sign of the number. In the 2 absolute equation equality, we are looking for values of the variable that would make both absolute expressions equal to each other.

4. How do you find the maximum and minimum values of x in the 2 absolute equation equality?

To find the maximum and minimum values of x in the 2 absolute equation equality, you need to consider all possible cases. This means setting up and solving the two separate equations, one with the positive value and one with the negative value of the absolute expressions. The maximum and minimum values of x would then be the solutions that satisfy both equations.

5. Are there any special cases to consider when solving the 2 absolute equation equality?

Yes, there are two special cases to consider when solving the 2 absolute equation equality. The first is when the absolute expressions are equal to each other, in which case there would be infinitely many solutions. The second is when the absolute expressions are both equal to 0, in which case there would be no solutions. These special cases should be checked for when solving the equations.

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