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Let, (x) = Least integer greater than or equal to x
       [x] = Greatest integer less than or equal to x
       |x| = absolute value of x,
Which of the following always holds good if x < 0?


Options:
A .   [|x|] = | [x ] |
B .   [|x|]<|[x]|
C .   [|x|]>|[x]|
D .   |x|<[x]
Answer: Option B
:
B
The right answer is [|x|]<|[x]|.
Let x = n + f where n is its integral part & f is its fractional part.
Hence, | x | = n + f if x is positive and | x | = - n - f if x is negative.
If x is - ve, then | x | = -n -f .
Hence,[ | x | ] = -n and | [x] | is always non negative.
Hence the alternative (2) holds good.
Method 2- Using assumption
Take a value say x= -1.4 (you can take anything!)
Thus, | - 1.4| = 1.4 and [1.4] = 1
Also, [ -1.4] = -2 and |-2| = 2
Glance at the answer options; the only one satisfying this assumption is [|x|]<|[x]|.

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