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=-1

解答

2 x^{2} + 7 x = - 1

解答

x = \frac{- 7 + 41}{4}, x = \frac{- 7 - 41}{4}

+1

十进制

x = - 0.14921 \dots, x = - 3.35078 \dots

求解步骤

2 x^{2} + 7 x = - 1

将

1

para o lado esquerdo

2 x^{2} + 7 x + 1 = 0

使用求根公式求解

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

7^{2} - 4 \cdot 2 \cdot 1 = 41

x_{1, 2} = \frac{- 7 \pm 41}{2 \cdot 2}

将解分隔开

x_{1} = \frac{- 7 + 41}{2 \cdot 2}, x_{2} = \frac{- 7 - 41}{2 \cdot 2}

x = \frac{- 7 + 41}{2 \cdot 2} : \frac{- 7 + 41}{4}

x = \frac{- 7 - 41}{2 \cdot 2} : \frac{- 7 - 41}{4}

二次方程组的解是:

x = \frac{- 7 + 41}{4}, x = \frac{- 7 - 41}{4}

作图

流行的例子

4 x^{2} - 40 x + 84 = 0

x^{2} + 4 x + (- 1) = 0

solvefor x,f=x^2+y^2+x(y-z)-4x-6y+4z+30

so l v e f or x, f = x^{2} + y^{2} + x (y - z) - 4 x - 6 y + 4 z + 30

solvefor A,(A+X)^2=BC

so l v e f or A, (A + X)^{2} = BC

quadraticformula x^2-x=0

q u a d r a t i c f or m u l a x^{2} - x = 0