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 >

0=x^2+5x+1

解答

0 = x^{2} + 5 x + 1

解答

x = \frac{- 5 + 21}{2}, x = \frac{- 5 - 21}{2}

+1

十进制

x = - 0.20871 \dots, x = - 4.79128 \dots

求解步骤

0 = x^{2} + 5 x + 1

交换两边

x^{2} + 5 x + 1 = 0

使用求根公式求解

x_{1, 2} = \frac{- 5 \pm 5 ^{2} - 4 \cdot 1 \cdot 1}{2 \cdot 1}

5^{2} - 4 \cdot 1 \cdot 1 = 21

x_{1, 2} = \frac{- 5 \pm 21}{2 \cdot 1}

将解分隔开

x_{1} = \frac{- 5 + 21}{2 \cdot 1}, x_{2} = \frac{- 5 - 21}{2 \cdot 1}

x = \frac{- 5 + 21}{2 \cdot 1} : \frac{- 5 + 21}{2}

x = \frac{- 5 - 21}{2 \cdot 1} : \frac{- 5 - 21}{2}

二次方程组的解是:

x = \frac{- 5 + 21}{2}, x = \frac{- 5 - 21}{2}

作图

流行的例子

(117-x)(333-x)-81^2=0

(117 - x) (333 - x) - 8 1^{2} = 0

solvefor x,(2x-1)^2=9(y^2+z^2)

so l v e f or x, (2 x - 1)^{2} = 9 (y^{2} + z^{2})

solvefor b,z=-(b^2x)/y

so l v e f or b, z = - \frac{b ^{2} x}{y}

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

x^{2} - 10 x - 67 = 8