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VTMO 2026 - Grade 9 - Semifinal - SET 07 - Self-study Question 17

VTMO · VTMO 2026 - Grade 9 - Semifinal - SET 07 - Self-study

Question 17

Let $A=\dfrac{20}{\sqrt2+\sqrt3+\sqrt7}$. Which identity is correct?
  1. $(\sqrt2-\sqrt3+\sqrt7)(2\sqrt6+2)$
  2. $(\sqrt2+\sqrt3-\sqrt7)(2\sqrt6+2)$
  3. $(\sqrt2+\sqrt3-\sqrt7)(2\sqrt6-2)$
  4. $(\sqrt2-\sqrt3+\sqrt7)(2\sqrt6-2)$
  5. $(\sqrt2-\sqrt3-\sqrt7)(2\sqrt6-2)$