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Inequality Equation Encounters (Posted on 2024-09-20) Difficulty: 3 of 5
Solve the inequality

|(x-3)(x-5)|≤|x(x-4)|

No Solution Yet Submitted by Danish Ahmed Khan    
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Solution Solution Comment 1 of 1
The LHS can be broken into parts:
(x-3)(x-5) on (-,3] or [5,)
-(x-3)(x-5) on (3,5)

The RHS similarly
x(x-4) on (-∞,0] or [4,∞)
-x(x-4) on (0,4)

This gives 5 regions
(1): (∞,0]
x^2-8x+15 <= x^2-4x
x >= 15/4 not in range

(2): (0,3)
x^2-8x+15 <= -x^2+4x
(6-sqrt6)/2 <= x <= (6+sqrt6)/2
in range then (6-sqrt6)/2 <= x < 3

(3): [3,4)
-x^2+8x-15 <= -x^2+4x
x <= 15/4
in range then 3 < x <= 15/4

(4): [4,5)
-x^2+8x-15 <= x^2-4x
x <= (6-sqrt(6))/2 or x>= (6+sqrt6)/2
in range then (6+sqrt6)/2 >= x >5

(5): [5,)
Same as (1)
but now all in range: x>=5

Put this all together for the Final answer:

(6-sqrt6)/2 <= x <= 15/4 or x >= (6+sqrt6)/2




  Posted by Jer on 2024-09-20 14:03:49
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