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Numbers System — MATHS STD 9 — Question

Rajasthan BoardEnglish MediumSTD 9MATHSNumbers System1 Mark
Question
$\big(-2-\sqrt{3}\big)\big(-2+\sqrt{3}\big)$ when simplified is:
  1. positive and irrational.
  2. positive and rational.
  3. negative and irrational.
  4. negative and rational.
✓

Answer

  1. positive and rational.
Solution:
$\big(-2-\sqrt{3}\big)\big(-2+\sqrt{3}\big)$
$\big(-2\big)^2-\big(\sqrt{3}\big)^2$
$=4-3=1,$ which is positive and rational number.
Hence, the correct answer is option (b).

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