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受欢迎的代数 >

2x^2+40=-8x

解答

2 x^{2} + 40 = - 8 x

解答

x = - 2 + 4 i, x = - 2 - 4 i

求解步骤

2 x^{2} + 40 = - 8 x

将

8 x

para o lado esquerdo

2 x^{2} + 40 + 8 x = 0

改写成标准形式

a x^{2} + b x + c = 0

2 x^{2} + 8 x + 40 = 0

使用求根公式求解

x_{1, 2} = \frac{- 8 \pm 8 ^{2} - 4 \cdot 2 \cdot 40}{2 \cdot 2}

化简

8^{2} - 4 \cdot 2 \cdot 40 : 16 i

x_{1, 2} = \frac{- 8 \pm 16 i}{2 \cdot 2}

将解分隔开

x_{1} = \frac{- 8 + 16 i}{2 \cdot 2}, x_{2} = \frac{- 8 - 16 i}{2 \cdot 2}

x = \frac{- 8 + 16 i}{2 \cdot 2} : - 2 + 4 i

x = \frac{- 8 - 16 i}{2 \cdot 2} : - 2 - 4 i

二次方程组的解是:

x = - 2 + 4 i, x = - 2 - 4 i

作图

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