SOLUTION: Help me answer this question please:
⌊1.25 + ⌊𝑥⌋⌋ = 12
I am completely unsure as I have no clue what that style of brakcets mean
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-> SOLUTION: Help me answer this question please:
⌊1.25 + ⌊𝑥⌋⌋ = 12
I am completely unsure as I have no clue what that style of brakcets mean
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Question 1106550: Help me answer this question please:
⌊1.25 + ⌊𝑥⌋⌋ = 12
I am completely unsure as I have no clue what that style of brakcets mean Answer by math_helper(2461) (Show Source):
You can put this solution on YOUR website! Those brackets indicate the "floor" function.
floor(x) = k where k is the greatest integer less than or equal to x; x is a real number, k is an integer.
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The question is asking to find x such that the floor( floor(x) + 1.25 ) = 12
The inner-most floor (floor(x)) is an integer, so we can re-write this problem using integer n:
floor(n + 1.25) = 12
if n = 10 we get floor(10 + 1.25) = floor(11.25) = 11 too low
if n = 11 we get floor(11 + 1.25) = floor(12.25) = 12 ok
Since the inner-most floor (floor(x)) is taken first in order to get the 11 in 11+1.25, x can be any value in the range
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Check:
x=11: floor(x) = floor(11) = 11 and floor(11+1.25) = floor(12.25) = 12 (ok)
x=12-s where 0 < s <= 1: floor(x) = floor(12-s) = floor(some number greater than or equal to 11, and less than 12) = 11 and floor(11+1.25) = floor(12.25) = 12 (ok)
You can also do negative checks by letting x=11-s and x=12 to see that those do not result in a final value of 12, to convince yourself the highlighted range captures all possible values of x.
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One thing about the floor() function, you must be very careful about your less than or equal signs.
A related function is the ceiling() function.
