## Encyclopedia > 1638

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# 1638

Years: 1633 1634 1635 1636 1637 - 1638 - 1639 1640 1641 1642 1643

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 Catastrophic loss of significance ... x_1 = \frac{-b + \sqrt{b^2 - 4ac}}{2a} [/itex] and $x_2 = \frac{-b - \sqrt{b^2 - 4ac}}{2a}$ then we hav ...