Tell me the first n terms of the process arithmetic sequence an and s, S16 > 0, S17 = 0. What is the maximum value of N in SN
because:s16= [16(a1+a16)/2]=[16(a8+a9)/2]>0
thus:a8+a9 >0
and:s17= [17(a1+a17/2)]=[17(a9+a9)/2]=0
im mediately:a9 >=0
so:a8>0 a9=0
now you kmow:sn The largest item is S8 or S9
best wish
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