已知二次函数y=x^2+mx+m-2 求证:无论m取任何实数,二次函数的图像总与x...
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答:8 = m�� - 4m + 4 + 4 = (m -2 )�� + 4 因为 无论m取任何实数,(m -2 )�� + 4 都大于0 所以,无论m取任何实数,二次函数的图像总与x轴有两个交点.