X^2+4X-5=0

解

X^{2} + 4 X - 5 = 0

X = 1, X = - 5

解答ステップ

X^{2} + 4 X - 5 = 0

解くとthe二次式

X_{1, 2} = \frac{- 4 \pm 4 ^{2} - 4 \cdot 1 \cdot ( - 5 )}{2 \cdot 1}

4^{2} - 4 \cdot 1 \cdot (- 5) = 6

X_{1, 2} = \frac{- 4 \pm 6}{2 \cdot 1}

解を分離する

X_{1} = \frac{- 4 + 6}{2 \cdot 1}, X_{2} = \frac{- 4 - 6}{2 \cdot 1}

X = \frac{- 4 + 6}{2 \cdot 1} : 1

X = \frac{- 4 - 6}{2 \cdot 1} : - 5

二次equationの解:

X = 1, X = - 5