化简:
(1)2a-[-3b-3(3a-b)];
(2)12ab2-[7a2b-(ab2-3a2b)].
(1)原式=2a-[-3b-9a+3b]=2a+9a=11a;
(2)原式=12ab2-[7a2b-ab2+3a2b]=12ab2-10a2b+ab2=13ab2-10a2b.
化简:
(1)2a-[-3b-3(3a-b)];
(2)12ab2-[7a2b-(ab2-3a2b)].
(1)原式=2a-[-3b-9a+3b]=2a+9a=11a;
(2)原式=12ab2-[7a2b-ab2+3a2b]=12ab2-10a2b+ab2=13ab2-10a2b.