a+b=-2,ab=3,求代数式(4ab-10b)-[7a-(3ab-3a)]值?
问题描述:
a+b=-2,ab=3,求代数式(4ab-10b)-[7a-(3ab-3a)]值?
答
(4ab-10b)-[7a-(3ab-3a)]=7ab-10b-10a=21-10*(-2)=41
a+b=-2,ab=3,求代数式(4ab-10b)-[7a-(3ab-3a)]值?
(4ab-10b)-[7a-(3ab-3a)]=7ab-10b-10a=21-10*(-2)=41