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 >

4+9n-3n^2=2-n

解答

4 + 9 n - 3 n^{2} = 2 - n

解答

n = - \frac{- 5 + 31}{3}, n = \frac{5 + 31}{3}

+1

十进制

n = - 0.18925 \dots, n = 3.52258 \dots

求解步骤

4 + 9 n - 3 n^{2} = 2 - n

将

n

para o lado esquerdo

- 3 n^{2} + 10 n + 4 = 2

将

2

para o lado esquerdo

- 3 n^{2} + 10 n + 2 = 0

使用求根公式求解

n_{1, 2} = \frac{- 10 \pm 1 0 ^{2} - 4 ( - 3 ) \cdot 2}{2 ( - 3 )}

1 0^{2} - 4 (- 3) \cdot 2 = 231

n_{1, 2} = \frac{- 10 \pm 2 31}{2 ( - 3 )}

将解分隔开

n_{1} = \frac{- 10 + 2 31}{2 ( - 3 )}, n_{2} = \frac{- 10 - 2 31}{2 ( - 3 )}

n = \frac{- 10 + 2 31}{2 ( - 3 )} : - \frac{- 5 + 31}{3}

n = \frac{- 10 - 2 31}{2 ( - 3 )} : \frac{5 + 31}{3}

二次方程组的解是:

n = - \frac{- 5 + 31}{3}, n = \frac{5 + 31}{3}

作图

流行的例子

25 x^{2} = 0

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

completesquare 9x^2+6x+1

co m pl e t es q u a re 9 x^{2} + 6 x + 1

x + 15 = x (x - 1)

solvefor x,x^2+7x=0

so l v e f or x, x^{2} + 7 x = 0