网址:http://m.1010jiajiao.com/timu_id_1647302[举报]
=
A.1 B.2 C.-1 D.-2
等于 ( )
A.1 B.2 C.-1 D.0
等于
1
2
-1
0
已知:
A.1 B.2 C.-2 D.
已知=( )