solvefor x,3x^2-mx+15=0

解

x, 3 x^{2} - m x + 15 = 0

x = \frac{m + m ^{2} - 180}{6}, x = \frac{m - m ^{2} - 180}{6}

解答ステップ

3 x^{2} - m x + 15 = 0

解くとthe二次式

x_{1, 2} = \frac{- ( - m ) \pm ( - m ) ^{2} - 4 \cdot 3 \cdot 15}{2 \cdot 3}

簡素化

(- m)^{2} - 4 \cdot 3 \cdot 15 : m^{2} - 180

x_{1, 2} = \frac{- ( - m ) \pm m ^{2} - 180}{2 \cdot 3}

解を分離する

x_{1} = \frac{- ( - m ) + m ^{2} - 180}{2 \cdot 3}, x_{2} = \frac{- ( - m ) - m ^{2} - 180}{2 \cdot 3}

x = \frac{- ( - m ) + m ^{2} - 180}{2 \cdot 3} : \frac{m + m ^{2} - 180}{6}

x = \frac{- ( - m ) - m ^{2} - 180}{2 \cdot 3} : \frac{m - m ^{2} - 180}{6}

二次equationの解:

x = \frac{m + m ^{2} - 180}{6}, x = \frac{m - m ^{2} - 180}{6}