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+5)(x-3)=(4x-7)^2

解答

(2 x + 5) (x - 3) = (4 x - 7)^{2}

解答

x = \frac{55}{28} - i \frac{559}{28}, x = \frac{55}{28} + i \frac{559}{28}

求解步骤

(2 x + 5) (x - 3) = (4 x - 7)^{2}

展开

(2 x + 5) (x - 3) : 2 x^{2} - x - 15

展开

(4 x - 7)^{2} : 16 x^{2} - 56 x + 49

2 x^{2} - x - 15 = 16 x^{2} - 56 x + 49

将

49

para o lado esquerdo

2 x^{2} - x - 64 = 16 x^{2} - 56 x

将

56 x

para o lado esquerdo

2 x^{2} + 55 x - 64 = 16 x^{2}

将

16 x^{2}

para o lado esquerdo

- 14 x^{2} + 55 x - 64 = 0

使用求根公式求解

x_{1, 2} = \frac{- 55 \pm 5 5 ^{2} - 4 ( - 14 ) ( - 64 )}{2 ( - 14 )}

化简

5 5^{2} - 4 (- 14) (- 64) : 559 i

x_{1, 2} = \frac{- 55 \pm 559 i}{2 ( - 14 )}

将解分隔开

x_{1} = \frac{- 55 + 559 i}{2 ( - 14 )}, x_{2} = \frac{- 55 - 559 i}{2 ( - 14 )}

x = \frac{- 55 + 559 i}{2 ( - 14 )} : \frac{55}{28} - i \frac{559}{28}

x = \frac{- 55 - 559 i}{2 ( - 14 )} : \frac{55}{28} + i \frac{559}{28}

二次方程组的解是:

x = \frac{55}{28} - i \frac{559}{28}, x = \frac{55}{28} + i \frac{559}{28}

作图

流行的例子

solvefor k,k^2+R/L k+1/(LC)=0

so l v e f or k, k^{2} + \frac{R}{L} k + \frac{1}{L C} = 0

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

36.75=(30-x)^2*0.5

36.75 = (30 - x)^{2} \cdot 0.5

completesquare 3x^2-12x+2

co m pl e t es q u a re 3 x^{2} - 12 x + 2

2(x-16)=(x-8)(x+2)

2 (x - 16) = (x - 8) (x + 2)