2z^2+6z-20=0

解

2 z^{2} + 6 z - 20 = 0

z = 2, z = - 5

解答ステップ

2 z^{2} + 6 z - 20 = 0

解くとthe二次式

z_{1, 2} = \frac{- 6 \pm 6 ^{2} - 4 \cdot 2 ( - 20 )}{2 \cdot 2}

6^{2} - 4 \cdot 2 (- 20) = 14

z_{1, 2} = \frac{- 6 \pm 14}{2 \cdot 2}

解を分離する

z_{1} = \frac{- 6 + 14}{2 \cdot 2}, z_{2} = \frac{- 6 - 14}{2 \cdot 2}

z = \frac{- 6 + 14}{2 \cdot 2} : 2

z = \frac{- 6 - 14}{2 \cdot 2} : - 5

二次equationの解:

z = 2, z = - 5