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=x+2

解答

2 x^{2} = x + 2

解答

x = \frac{1 + 17}{4}, x = \frac{1 - 17}{4}

+1

十进制

x = 1.28077 \dots, x = - 0.78077 \dots

求解步骤

2 x^{2} = x + 2

将

2

para o lado esquerdo

2 x^{2} - 2 = x

将

x

para o lado esquerdo

2 x^{2} - 2 - x = 0

改写成标准形式

a x^{2} + b x + c = 0

2 x^{2} - x - 2 = 0

使用求根公式求解

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

(- 1)^{2} - 4 \cdot 2 (- 2) = 17

x_{1, 2} = \frac{- ( - 1 ) \pm 17}{2 \cdot 2}

将解分隔开

x_{1} = \frac{- ( - 1 ) + 17}{2 \cdot 2}, x_{2} = \frac{- ( - 1 ) - 17}{2 \cdot 2}

x = \frac{- ( - 1 ) + 17}{2 \cdot 2} : \frac{1 + 17}{4}

x = \frac{- ( - 1 ) - 17}{2 \cdot 2} : \frac{1 - 17}{4}

二次方程组的解是:

x = \frac{1 + 17}{4}, x = \frac{1 - 17}{4}

作图

流行的例子

s^{2} + 9 s + 9 = 0

completesquare x^2+2x+4=0

co m pl e t es q u a re x^{2} + 2 x + 4 = 0

solvefor x,9x^2=4y^3

so l v e f or x, 9 x^{2} = 4 y^{3}

x^2+17x+12=-3x^2

x^{2} + 17 x + 12 = - 3 x^{2}

(x - 4) (x + 4) = 9