先去括号,再合并同类项.(5a³-2a²-3)-(1-3a²+2a³)-(-2a³+a²-4).今天就要,明天要交的,

问题描述:

先去括号,再合并同类项.
(5a³-2a²-3)-(1-3a²+2a³)-(-2a³+a²-4).
今天就要,明天要交的,

(5a³-2a²-3)-(1-3a²+2a³)-(-2a³+a²-4)
=5a³-2a²-3-1+3a²-2a³+2a³-a²+4
=10a³-3a²

(5a³-2a²-3)-(1-3a²+2a³)-(-2a³+a²-4)
=5a³-2a²-3-1+3a²-2a³+2a³-a²+4
=5a³