bentuk rasional dari 4/1-akar 2

[tex] \frac{4}{1 - \sqrt{2} } = \frac{4}{1 - \sqrt{2} } \times \frac{1 + \sqrt{2} }{1 + \sqrt{2} } \\ = \frac{4(1 + \sqrt{2}) }{1 - 2} \\ = \frac{4(1 + \sqrt{2} )}{ - 1} \\ = - 4(1 + \sqrt{2} ) = - 4 - 4 \sqrt{2} [/tex]