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If x = 4+2√2, then find (x-8+8/x). |
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Answer» \(x = 4 + 2\sqrt 2\) \(\frac 1x = \frac1{4 + 2\sqrt 2} = \frac {4 - 2\sqrt 2}{(4 + 2\sqrt 2) (4 - 2\sqrt 2)}\) \(= \frac {4 - 2\sqrt 2}{16 - 8}\) \(= \frac{4 - 2\sqrt 2}8\) \(\therefore x - 8 + \frac 8x = 4 + 2\sqrt 2 - 8 + 4 - 2\sqrt2 = 0\) |
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