已知A=7ab-3a^2b^2+7+8ab^2,B=3a^2b^2-3-7ab,则A-B=( )
问题描述:
已知A=7ab-3a^2b^2+7+8ab^2,B=3a^2b^2-3-7ab,则A-B=( )
答
A-B=(7ab-3a^2b^2+7+8ab^2)-(3a^2b^2-3-7ab)
=7ab-3a^2b^2+7+8ab^2-3a^2b^2+3+7ab
=14ab-6a^2b^2+8ab^2+10