zs

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

受欢迎的代数 >

2x-5(x+3)=x(x-4)

解答

2 x - 5 (x + 3) = x (x - 4)

解答

x = \frac{1}{2} + i \frac{59}{2}, x = \frac{1}{2} - i \frac{59}{2}

求解步骤

2 x - 5 (x + 3) = x (x - 4)

展开

2 x - 5 (x + 3) : - 3 x - 15

展开

x (x - 4) : x^{2} - 4 x

- 3 x - 15 = x^{2} - 4 x

交换两边

x^{2} - 4 x = - 3 x - 15

将

15

para o lado esquerdo

x^{2} - 4 x + 15 = - 3 x

将

3 x

para o lado esquerdo

x^{2} - x + 15 = 0

使用求根公式求解

x_{1, 2} = \frac{- ( - 1 ) \pm ( - 1 ) ^{2} - 4 \cdot 1 \cdot 15}{2 \cdot 1}

化简

(- 1)^{2} - 4 \cdot 1 \cdot 15 : 59 i

x_{1, 2} = \frac{- ( - 1 ) \pm 59 i}{2 \cdot 1}

将解分隔开

x_{1} = \frac{- ( - 1 ) + 59 i}{2 \cdot 1}, x_{2} = \frac{- ( - 1 ) - 59 i}{2 \cdot 1}

x = \frac{- ( - 1 ) + 59 i}{2 \cdot 1} : \frac{1}{2} + i \frac{59}{2}

x = \frac{- ( - 1 ) - 59 i}{2 \cdot 1} : \frac{1}{2} - i \frac{59}{2}

二次方程组的解是:

x = \frac{1}{2} + i \frac{59}{2}, x = \frac{1}{2} - i \frac{59}{2}

作图

流行的例子

3 x + 4 = 2 x^{2} - 7

407x^2+480x-69=0

407 x^{2} + 480 x - 69 = 0

(2x+5)(6x-1)=120

(2 x + 5) (6 x - 1) = 120

24 x^{2} - 82 x + 48 = 0

5 y^{2} = 80