若a+b=3,ab=-2,则(4a-5b-3ab)-(3a-6b+ab)=_.
问题描述:
若a+b=3,ab=-2,则(4a-5b-3ab)-(3a-6b+ab)=______.
答
∵a+b=3,ab=-2,
(4a-5b-3ab)-(3a-6b+ab)
=4a-5b-3ab-3a+6b-ab
=a+b-4ab
=3-4×(-2)
=11,
故答案为:11.