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受欢迎的代数 >

(x)=x^2-6x+8

解答

(x) = x^{2} - 6 x + 8

解答

x = \frac{7 + 17}{2}, x = \frac{7 - 17}{2}

+1

十进制

x = 5.56155 \dots, x = 1.43844 \dots

求解步骤

(x) = x^{2} - 6 x + 8

整理后得

x = x^{2} - 6 x + 8

交换两边

x^{2} - 6 x + 8 = x

将

x

para o lado esquerdo

x^{2} - 7 x + 8 = 0

使用求根公式求解

x_{1, 2} = \frac{- ( - 7 ) \pm ( - 7 ) ^{2} - 4 \cdot 1 \cdot 8}{2 \cdot 1}

(- 7)^{2} - 4 \cdot 1 \cdot 8 = 17

x_{1, 2} = \frac{- ( - 7 ) \pm 17}{2 \cdot 1}

将解分隔开

x_{1} = \frac{- ( - 7 ) + 17}{2 \cdot 1}, x_{2} = \frac{- ( - 7 ) - 17}{2 \cdot 1}

x = \frac{- ( - 7 ) + 17}{2 \cdot 1} : \frac{7 + 17}{2}

x = \frac{- ( - 7 ) - 17}{2 \cdot 1} : \frac{7 - 17}{2}

二次方程组的解是:

x = \frac{7 + 17}{2}, x = \frac{7 - 17}{2}

作图

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