解:原式= 2+32-32+3
——Did you hear that water in Tai Lake smelled terrible?——Yes.It ___________ because of people and factories.
关于我国夏季气温的叙述正确的是( )
设命题p:∀x∈R,x2+1>0 ,则 ¬p 为( )
已知(-5,π3),下列所给出的不能表示此点的坐标的是( )