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Write the roster (tabular) form of the set A = {x: x is a natural number and x² < 30}.

1. {1, 2, 3, 4, 5}
2. {0, 1, 2, 3, 4, 5}
3. {-5, -4, -3,.... 4, 5}
4. None of these

Correct answer: {1, 2, 3, 4, 5}

Solution

Natural numbers satisfying x² < 30 are 1, 2, 3, 4, 5 (since 5² = 25 < 30 and 6² = 36 > 30). Zero is not a natural number in the standard Indian curriculum definition.

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