Rationalising factor of $\sqrt{a} - \sqrt{b}$ is

Rationalising factor of $\sqrt{a} - \sqrt{b}$ is
  1. $\sqrt{a} + \sqrt{b}$
  2. $\sqrt{a} - \sqrt{b}$
  3. $\sqrt{ab}$
  4. $a - b$

Solution

Conjugate $\sqrt{a} + \sqrt{b}$ gives $(\sqrt{a})^{2} - (\sqrt{b})^{2} = a - b$.

Asked in: MH-SSC-9

Practice more Real Numbers questions on Aicharya