-4r^2+16r=0

解

- 4 r^{2} + 16 r = 0

r = 0, r = 4

解答ステップ

- 4 r^{2} + 16 r = 0

解くとthe二次式

r_{1, 2} = \frac{- 16 \pm 1 6 ^{2} - 4 ( - 4 ) \cdot 0}{2 ( - 4 )}

1 6^{2} - 4 (- 4) \cdot 0 = 16

r_{1, 2} = \frac{- 16 \pm 16}{2 ( - 4 )}

解を分離する

r_{1} = \frac{- 16 + 16}{2 ( - 4 )}, r_{2} = \frac{- 16 - 16}{2 ( - 4 )}

r = \frac{- 16 + 16}{2 ( - 4 )} : 0

r = \frac{- 16 - 16}{2 ( - 4 )} : 4

二次equationの解:

r = 0, r = 4