-a^2-a+2=0

解

- a^{2} - a + 2 = 0

a = - 2, a = 1

解答ステップ

- a^{2} - a + 2 = 0

解くとthe二次式

a_{1, 2} = \frac{- ( - 1 ) \pm ( - 1 ) ^{2} - 4 ( - 1 ) \cdot 2}{2 ( - 1 )}

(- 1)^{2} - 4 (- 1) \cdot 2 = 3

a_{1, 2} = \frac{- ( - 1 ) \pm 3}{2 ( - 1 )}

解を分離する

a_{1} = \frac{- ( - 1 ) + 3}{2 ( - 1 )}, a_{2} = \frac{- ( - 1 ) - 3}{2 ( - 1 )}

a = \frac{- ( - 1 ) + 3}{2 ( - 1 )} : - 2

a = \frac{- ( - 1 ) - 3}{2 ( - 1 )} : 1

二次equationの解:

a = - 2, a = 1