求代数式a³-(-a²+2a-1)= 的值a³-(-a²+2a-1)= ﹙_________﹚+(a²+1)
问题描述:
求代数式a³-(-a²+2a-1)= 的值
a³-(-a²+2a-1)= ﹙_________﹚+(a²+1)
答
a(a²-2)
答
a³-(-a²+2a-1)=﹙a³-2a﹚+(a²+1)
答
-2a+1
答
a³-2a
答
a³-(-a²+2a-1)
= a³+a²-2a+1 (除括号)
=a³-2a+a²+1 (移项,符号连同一起移)
=(a³-2a)+(a²+1)