9.化简下列各题:
(1)$\frac{1}{2}$x+3(-2x+y)-($\frac{1}{3}$x-4y-5z)
(2)a2b-[2(a2b-2a2c]-(2b2c-a2c).
分析 (1)去括号,合并同类项即可;
(2)先去括号,再合并同类项即可.
解答 解:(1)原式=$\frac{1}{2}$x-6x+3y-$\frac{1}{3}$x+4y+5z
=-$\frac{35}{6}$x+7y+5z;
(2)原式=a2b-[2a2b-4a2c-2b2c+a2c]
=a2b-2a2b+4a2c+2b2c-a2c
=-a2b+3a2c+2b2c.
点评 本题考查了整式的加减的应用,能正确合并同类项是解此题的关键.