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^2+7x=-9

解答

2 x^{2} + 7 x = - 9

解答

x = - \frac{7}{4} + i \frac{23}{4}, x = - \frac{7}{4} - i \frac{23}{4}

求解步骤

2 x^{2} + 7 x = - 9

将

9

para o lado esquerdo

2 x^{2} + 7 x + 9 = 0

使用求根公式求解

x_{1, 2} = \frac{- 7 \pm 7 ^{2} - 4 \cdot 2 \cdot 9}{2 \cdot 2}

化简

7^{2} - 4 \cdot 2 \cdot 9 : 23 i

x_{1, 2} = \frac{- 7 \pm 23 i}{2 \cdot 2}

将解分隔开

x_{1} = \frac{- 7 + 23 i}{2 \cdot 2}, x_{2} = \frac{- 7 - 23 i}{2 \cdot 2}

x = \frac{- 7 + 23 i}{2 \cdot 2} : - \frac{7}{4} + i \frac{23}{4}

x = \frac{- 7 - 23 i}{2 \cdot 2} : - \frac{7}{4} - i \frac{23}{4}

二次方程组的解是:

x = - \frac{7}{4} + i \frac{23}{4}, x = - \frac{7}{4} - i \frac{23}{4}

作图

流行的例子

5 k^{2} + 28 = 27 k

7 x^{2} + 8 x = x^{2}

- x^{2} + 6 x + 10 = 0

2 x^{2} + 16 x + 32 = 0

(x+2)^2+(x-3)^2=9

(x + 2)^{2} + (x - 3)^{2} = 9