|4x-2| < |x-2|.
When x
< 1/2 , |4x-2| < |x-2| implies 2-4x <
2-x.
0 < 3x
x >
0 when x < 1/2. So 0 < x < 1/2 is a
solution.
When x = 1/2, 0 < |x-2|
==> 0 < 2-x . So x < 2. Therefore , x = 1/2
is a solution. (Please note that the symbol ==> stands for
implies, as the symbol , => looks like equal or greater
than.)
When 1/2 < x < 2, |4x-2| <
|x-2| ==> 4x-2 < 2-x , or 5x < 4 . So x < 4/5 is a
solution. Therefore 1/2 < x < 4/5 is a
solution.
When x = 2. |4x-2| < |x-2|
==> 4x-2 < 0, or x < 2/4. So x = 1/2. But x = 1/2 is a solution
already covered. But x = 1/2 when x = 2 is
contradiction.
When x > 2, |4x-2| < |x-2|
==> 4x-2 > x-2 , Or 4x-x = 0, or x= 0 does not go together with when x
> 2.
So the solution is 0 <
x 1/2 or 1/2 < x <
4/5.
Combining we get: 0
< x < 4/5 is a
solution.
Therefore solution set is ] 0
, 4/5 [ which is both left open and right open interval
.
Tally :
We take a value x
< 0, say x = -2, |4x-2| = |4*-2-2| = |-10| = 10. The RHS = |-4-2| = 6. So 10
> 6 the inequality does not hold.
At x = 0, we get
LHS |4*0-2| = 2 and RHS |0-2 | = 2. So it becomes an equality.
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