x-1-1-x-4-x-1-1-x-

Question Number 147893 by mathdanisur last updated on 24/Jul/21

x + 1 + \frac{1}{x} = 4 \Rightarrow x + 1 - \frac{1}{x} = ?

Commented by aliibrahim1 last updated on 24/Jul/21

x + \frac{1}{x} = 3 ⇛ {(x + \frac{1}{x})}^{2} = 3^{2}

x^{2} + \frac{1}{x^{2}} + 2 = 9

x^{2} + \frac{1}{x^{2}} - 2 = 5

{(x - \frac{1}{x})}^{2} = 5 ⇛ x - \frac{1}{x} = \sqrt{5}

x - \frac{1}{x} + 1 = \sqrt{5} + 1

Commented by mathdanisur last updated on 24/Jul/21

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