quadraticformula x^2-2x-2=0

解

x^{2} - 2 x - 2 = 0

x = 1 + 3, x = 1 - 3

十進法表記

x = 2.73205 \dots, x = - 0.73205 \dots

解答ステップ

x^{2} - 2 x - 2 = 0

解くとthe二次式

x_{1, 2} = \frac{- ( - 2 ) \pm ( - 2 ) ^{2} - 4 \cdot 1 \cdot ( - 2 )}{2 \cdot 1}

(- 2)^{2} - 4 \cdot 1 \cdot (- 2) = 23

x_{1, 2} = \frac{- ( - 2 ) \pm 2 3}{2 \cdot 1}

解を分離する

x_{1} = \frac{- ( - 2 ) + 2 3}{2 \cdot 1}, x_{2} = \frac{- ( - 2 ) - 2 3}{2 \cdot 1}

x = \frac{- ( - 2 ) + 2 3}{2 \cdot 1} : 1 + 3

x = \frac{- ( - 2 ) - 2 3}{2 \cdot 1} : 1 - 3

二次equationの解:

x = 1 + 3, x = 1 - 3