v^2+20v+84=0

解

v^{2} + 20 v + 84 = 0

v = - 6, v = - 14

解答ステップ

v^{2} + 20 v + 84 = 0

解くとthe二次式

v_{1, 2} = \frac{- 20 \pm 2 0 ^{2} - 4 \cdot 1 \cdot 84}{2 \cdot 1}

2 0^{2} - 4 \cdot 1 \cdot 84 = 8

v_{1, 2} = \frac{- 20 \pm 8}{2 \cdot 1}

解を分離する

v_{1} = \frac{- 20 + 8}{2 \cdot 1}, v_{2} = \frac{- 20 - 8}{2 \cdot 1}

v = \frac{- 20 + 8}{2 \cdot 1} : - 6

v = \frac{- 20 - 8}{2 \cdot 1} : - 14

二次equationの解:

v = - 6, v = - 14