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Answer» |X - 1| + |x - 2| + |x - 3| ≥ 6
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|x - 1| = (x - 1) when x ≥ 1
= - (x - ) when x < 1
|x - 2| = (x - 2) when x ≥ 2
= - (x - 2) when x < 2
|x - 3| = (x -3) when x ≥ 3
= - (x - 3) when x < 3
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for x < 1
|x - 1| + |x - 2| + |x - 3| ≥ 6
= - (x - 1) - (x - 2) - (x - 3) ≥ 6
= - 3x + 6 ≥ 6
add ( - 6) on both sides
= > - 3x ≥ 0
multiply by ( - 1) both sides (equality will be reversed) = > 3x ≤ 0 divide both sides by 3
= > x ≤ 0
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for 1 ≤ x < 2
|x - 1| + |x - 2| + |x - 3| ≥ 6
= (x - 1) - (x - 2) - (x - 3) ≥ 6
= - x + 4 ≥ 6
subtract 4 on both sides
= > - x ≥ 2
multiply by ( - 1) both sides (equality will change)
= x ≤ - 2
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for 2 ≤ x < 3
|x - 1| + |x - 2| + |x - 3| ≥ 6
= (x - 1) + (x - 2) - (x - 3) ≥ 6
= x ≥ 6
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for x ≥ 3
|x - 1| + |x - 2| + |x - 3| > 6
= (x - 1) + (x - 2) + (x - 3) > 6
= 3x - 6 ≥ 6
add 6 on both sides
= > 3x ≥ 12 divide by 3 on both sides
= > x ≥ 4
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on combining the ranges we GET
x ≤ 0 or x ≥ 4
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