2y^2-6y-8=0

解

2 y^{2} - 6 y - 8 = 0

y = 4, y = - 1

解答ステップ

2 y^{2} - 6 y - 8 = 0

解くとthe二次式

y_{1, 2} = \frac{- ( - 6 ) \pm ( - 6 ) ^{2} - 4 \cdot 2 ( - 8 )}{2 \cdot 2}

(- 6)^{2} - 4 \cdot 2 (- 8) = 10

y_{1, 2} = \frac{- ( - 6 ) \pm 10}{2 \cdot 2}

解を分離する

y_{1} = \frac{- ( - 6 ) + 10}{2 \cdot 2}, y_{2} = \frac{- ( - 6 ) - 10}{2 \cdot 2}

y = \frac{- ( - 6 ) + 10}{2 \cdot 2} : 4

y = \frac{- ( - 6 ) - 10}{2 \cdot 2} : - 1

二次equationの解:

y = 4, y = - 1