簡約 [x-1(x+2)]-(3x+1)

解

簡約

[x - 1 (x + 2)] - (3 x + 1)

- 3 x - 3

解答ステップ

(x - 1 \cdot (x + 2)) - (3 x + 1)

規則を適用する:

(a) = a

(x - 1 \cdot (x + 2)) = x - 1 \cdot (x + 2)

= x - 1 \cdot (x + 2) - (3 x + 1)

1 \cdot (x + 2) = x + 2

- (3 x + 1) = - 3 x - 1

= x - (x + 2) - 3 x - 1

拡張

- (x + 2) : - x - 2

= x - x - 2 - 3 x - 1

条件のようなグループ

= x - x - 3 x - 2 - 1

類似した元を足す:

x - x - 3 x = - 3 x

= - 3 x - 2 - 1

数を引く:

- 2 - 1 = - 3

= - 3 x - 3