Correct Notation for Intersections of Real Numbers Sets

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The discussion focuses on the correct notation for expressing the intersection of two sets of real numbers. The initial notation proposed is \{ x \in R |x \ge 0\} \cap \{ x \in R |3 \ge x\} = \{ x \in R |3 \ge x \ge 0\}. Participants suggest that a more conventional format would be \{x \in R |0 \le x \le 3\}, which is clearer for readers accustomed to a left-to-right number line. The consensus indicates that while the original notation is not incorrect, the alternative is preferable for readability. Overall, the discussion emphasizes clarity in mathematical notation for intersections of sets.
danago
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Lets say i have two sets of numbers (dealing with real numbers only):

<br /> \{ x \in R |x \ge 0\} <br />
<br /> \{ x \in R |3 \ge x\} <br />

And i want to show what the common values in the two sets are. Would my notation be correct if i wrote:

<br /> \{ x \in R |x \ge 0\} \cap \{ x \in R |3 \ge x\} = \{ x \in R |3 \ge x \ge 0\} <br />


Thanks in advance,
Dan.
 
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One would normally write the double inequality in increasing size: \{x\in\mathbb{R}:0\leq x\leq3\}
 
That is not incorrect but I suspect those who are used to a number line that goes from left to right would find it momentarily confusing!

Most people would find it easier to read
\{ x \in R |0 \le x \le 3\}
 
Ok that's fair enough, easy enough to change :smile:

But besides that, everything else ok?

Thanks for the replies.
 
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