Determine a and b

Determine rational numbers \(a\) and \(b\)

\[ \frac{4 + \sqrt{2}}{2 + \sqrt{2}} = a – \sqrt{b} \]

Solution:

\[ \frac{4 + \sqrt{2}}{2 + \sqrt{2}} \times \frac{2 – \sqrt{2}}{2 – \sqrt{2}} \]

\[ = \frac{(4 + \sqrt{2})(2 – \sqrt{2})}{(2)^2 – (\sqrt{2})^2} \]

\[ = \frac{8 – 4\sqrt{2} + 2\sqrt{2} – 2}{4 – 2} \]

\[ = \frac{6 – 2\sqrt{2}}{2} \]

\[ = 3 – \sqrt{2} \]

Comparing with \(a – \sqrt{b}\)

\[ a = 3, \quad b = 2 \]

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