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已知方程a3-5a2+3a=0三个根分别为a1,a2,a3,则计算a1(a2+a...
已知方程a3-5a2+3a=0三个根分别为a1,a2,a3,则计算a1(a2+a3)+a2(a1+a3)+a3(a1+a2)的值( )
A.-5
B.6
C.-6
D.3
考点分析:
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