z^2-13z-30=0

解

z^{2} - 13 z - 30 = 0

z = 15, z = - 2

解答ステップ

z^{2} - 13 z - 30 = 0

解くとthe二次式

z_{1, 2} = \frac{- ( - 13 ) \pm ( - 13 ) ^{2} - 4 \cdot 1 \cdot ( - 30 )}{2 \cdot 1}

(- 13)^{2} - 4 \cdot 1 \cdot (- 30) = 17

z_{1, 2} = \frac{- ( - 13 ) \pm 17}{2 \cdot 1}

解を分離する

z_{1} = \frac{- ( - 13 ) + 17}{2 \cdot 1}, z_{2} = \frac{- ( - 13 ) - 17}{2 \cdot 1}

z = \frac{- ( - 13 ) + 17}{2 \cdot 1} : 15

z = \frac{- ( - 13 ) - 17}{2 \cdot 1} : - 2

二次equationの解:

z = 15, z = - 2