Venn Diagram - Number System:

The number is . Radicand is 18.

The square root of is not a perfect square and the decimal

() of the number is not repeating, so the number is

an irrational number (I).

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•    Observe the Venn diagram:
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•     All irrational numbers (I) are real numbers (R).
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The number belongs to I, and R.