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Mathematics — Standard (041) — CBSE Class 10 board question

Q1. [1] § 1.4 Summary
For any prime number p, if p divides $a^2$, where a is any real number then p also divides
  1. A $a$
  2. B $a^{\frac{1}{2}}$
  3. C $a^{\frac{3}{2}}$
  4. D $a^{\frac{1}{8}}$
Previously asked in CBSE board exam
2025 30/5/1 Q3
Generated by claude-sonnet-4-6 · 2026-06-15 10:30 · grounding rag
Model Answer

Option A: $a$

By Theorem 1.2, if $p$ is a prime and $p$ divides $a^2$, then $p$ divides $a$, where $a$ is a positive integer.

Source: Chapter 1, Section 1.3 (Theorem 1.2)

Explanation

This is a direct application of Theorem 1.2 from the textbook. The theorem states specifically that if a prime $p$ divides $a^2$, it must divide $a$ itself (not any fractional power of $a$). The other options involve fractional indices which are not integers, so the theorem does not apply to them. For MCQs like this, simply recall the exact theorem statement.

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