Exercise · ZW-CARDINAL-NUMBER-008 · ★★☆ Intermediate

What is the cardinal of the set of integers \(x\) with \(-3\le x\le 4\)?

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Explanation

Both endpoints are included. From \(-3\) to \(4\) there are \(4-(-3)+1=8\) integers.

The cardinal number of a set \(A\) is the least ordinal equinumerous with \(A\). It measures the size of \(A\) and also works for infinite sets.

\[|A| = \min\{\alpha \in \mathrm{Ord} : \alpha \approx A\}\]