a-b=2,ab=1,则-6ab+3a+(-3)b等于多少?速求答案!

问题描述:

a-b=2,ab=1,则-6ab+3a+(-3)b等于多少?速求答案!

原式=-6ab+3a-3b
=-6ab+3(a-b)
=-6×1+3×2
=0

-6ab+3a+(-3)b
=-6+3(a-b)
=-6+6
=0