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

AI Thread Summary
The discussion revolves around solving the inequalities 2x - 1 >= 0 and x - 2 >= 0 to find the maximum and minimum values of x. Initial calculations suggested that the minimum was 1/3 and the maximum was 5/3. However, a contradiction was identified in the case where x >= 2, leading to the conclusion that this scenario is invalid. Ultimately, the correct minimum value of x is 1/3, and the maximum value is 1. The final consensus confirms these values as the accurate solutions.
Helly123
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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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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.
 
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
 
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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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.
 
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