4u^2-28u=0

解

4 u^{2} - 28 u = 0

u = 7, u = 0

解答ステップ

4 u^{2} - 28 u = 0

解くとthe二次式

u_{1, 2} = \frac{- ( - 28 ) \pm ( - 28 ) ^{2} - 4 \cdot 4 \cdot 0}{2 \cdot 4}

(- 28)^{2} - 4 \cdot 4 \cdot 0 = 28

u_{1, 2} = \frac{- ( - 28 ) \pm 28}{2 \cdot 4}

解を分離する

u_{1} = \frac{- ( - 28 ) + 28}{2 \cdot 4}, u_{2} = \frac{- ( - 28 ) - 28}{2 \cdot 4}

u = \frac{- ( - 28 ) + 28}{2 \cdot 4} : 7

u = \frac{- ( - 28 ) - 28}{2 \cdot 4} : 0

二次equationの解:

u = 7, u = 0