【简答题】如果关于x的一元二次方程ax 2 +bx+c=0(a≠0)中的二次项系数与常数项之和等于一次项系数,求证:-1必是该方程的一个根.
【简答题】如果关于x的一元二次方程ax 2 +bx+c=0(a≠0)中的二次项系数与常数项之和等于一次项系数, 求证:-1必是该方程的一个根。
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【简答题】Directions: For this part, you are allowed 30 minutes to write an essay with the title Starting Up Businesses after Graduation. You are required to write at least 120 words, following the outline give...
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