solvefor x,8x^2-kx+2=0

解

x, 8 x^{2} - k x + 2 = 0

x = \frac{k + k ^{2} - 64}{16}, x = \frac{k - k ^{2} - 64}{16}

解答ステップ

8 x^{2} - k x + 2 = 0

解くとthe二次式

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

簡素化

(- k)^{2} - 4 \cdot 8 \cdot 2 : k^{2} - 64

x_{1, 2} = \frac{- ( - k ) \pm k ^{2} - 64}{2 \cdot 8}

解を分離する

x_{1} = \frac{- ( - k ) + k ^{2} - 64}{2 \cdot 8}, x_{2} = \frac{- ( - k ) - k ^{2} - 64}{2 \cdot 8}

x = \frac{- ( - k ) + k ^{2} - 64}{2 \cdot 8} : \frac{k + k ^{2} - 64}{16}

x = \frac{- ( - k ) - k ^{2} - 64}{2 \cdot 8} : \frac{k - k ^{2} - 64}{16}

二次equationの解:

x = \frac{k + k ^{2} - 64}{16}, x = \frac{k - k ^{2} - 64}{16}