(a－b)²＝a²－2ab ＋b ²
aba2abb15622.lofter.com
+
关注
注册LOFTER
下载LOFTER App
安装iPad客户端
分享
关注
注册LOFTER
this.p={permalink:'4c7da671_2bbb0962d',userId:0,blogId:1283303025,postId:0, blogLink: 'https://aba2abb15622.lofter.com/'}
