k^2+3k-54=0

解

k^{2} + 3 k - 54 = 0

k = 6, k = - 9

解答ステップ

k^{2} + 3 k - 54 = 0

解くとthe二次式

k_{1, 2} = \frac{- 3 \pm 3 ^{2} - 4 \cdot 1 \cdot ( - 54 )}{2 \cdot 1}

3^{2} - 4 \cdot 1 \cdot (- 54) = 15

k_{1, 2} = \frac{- 3 \pm 15}{2 \cdot 1}

解を分離する

k_{1} = \frac{- 3 + 15}{2 \cdot 1}, k_{2} = \frac{- 3 - 15}{2 \cdot 1}

k = \frac{- 3 + 15}{2 \cdot 1} : 6

k = \frac{- 3 - 15}{2 \cdot 1} : - 9

二次equationの解:

k = 6, k = - 9