(1) 6xy^2-{3x^y-[2xy^-(5xy^2-4xy^2)]},其中x=3,y=-1
问题描述：
(1) 6xy^2-{3x^y-[2xy^-(5xy^2-4xy^2)]},其中x=3,y=-1
(2) 3a^2b-3(ab^2+3/5a^2b)-a^2b
是2
答
(1) 6xy^2-{3x^2y-[2xy^2-(5xy^2-4xy^2)]},其中x=3,y=-1
=6xy^2-{3x^2y-[2xy^2-xy^2]} =6xy^2-{3x^2y-xy^2}=6xy^2-3x^2y+xy^2=7xy^2-3x^2y=7*3*(-1)^2-3*3^2*(-1)
=21+27
=48
(2) 3a^2b-3(ab^2+3/5a^2b)-a^2b=3a^2b-3ab^2-9/5a^2b-a^2b=1/5a^2b-3ab^2