若|m+2|+(n-1)2=0,则m+2n的值为( )
A:-5
B:-1
C:0
D:4
已知无穷等比数列{an}的公比为q,前n项和为Sn,且 limn→∞Sn=S,下列条件中,使得2Sn<S(n∈N*)恒成立的是( )
21÷3=____
下列说法错误的一项是( )
Could you tell me answer to this question? I can't work it out myself.