已知关于x的二次方程x2+2mx+2m+1=0,若方程有两根,其中一根在区间(﹣1,0)内,另一根在区间(1,2)内,m的范围是____
若sinα<0,且tanα>0,则α是第____ 象限角.
— Mum, can you give me some advice on how to behave myself at the table?
— Well, I do have some advice. , please keep quiet while eating.
被誉为地球之肾的生态系统是( )