9r^2+6r+1=0

解

9 r^{2} + 6 r + 1 = 0

r = - \frac{1}{3}

十進法表記

r = - 0.33333 \dots

解答ステップ

9 r^{2} + 6 r + 1 = 0

解くとthe二次式

r_{1, 2} = \frac{- 6 \pm 6 ^{2} - 4 \cdot 9 \cdot 1}{2 \cdot 9}

6^{2} - 4 \cdot 9 \cdot 1 = 0

r_{1, 2} = \frac{- 6 \pm 0}{2 \cdot 9}

r = \frac{- 6}{2 \cdot 9}

\frac{- 6}{2 \cdot 9} = - \frac{1}{3}

r = - \frac{1}{3}

二次equationの解:

r = - \frac{1}{3}