MHB When does the floor function inequality hold?

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The floor function inequality claim states that [x] ≥ x - 1, where [x] represents the integral part of x. While the strict inequality [x] > x - 1 is valid, equality does not occur for any value of x. The discussion confirms that the original claim remains true as a weaker statement, despite the absence of equality. Thus, the inequality holds, but equality is impossible. The conclusion emphasizes the validity of the claim while clarifying the nature of the inequality.
SweatingBear
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Let [x] be the floor function i.e. it produces the integral part of x. So for example if x = 1.5 then [x] = 1. I recently saw the claim

$$[x] \geq x - 1$$

The strict part of the inequality makes perfect sense, but when does equality occur? Does it even occur at all? I have not been able to find an example. Maybe the claim is false?
 
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sweatingbear said:
Let [x] be the floor function i.e. it produces the integral part of x. So for example if x = 1.5 then [x] = 1. I recently saw the claim

$$[x] \geq x - 1$$

The strict part of the inequality makes perfect sense, but when does equality occur? Does it even occur at all? I have not been able to find an example. Maybe the claim is false?

Hi sweatingbear!

You are right that equality cannot occur.
However, the claim is still true.
Consider that:
$$[x] > x - 1 \quad\Rightarrow\quad [x] \geq x - 1$$
It's just a weaker statement. Still true though.
 
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