we know that a(n)=4n+1 To find the sum of the first n terms of an arithmetic series use the formula Sn=n(a1 + an)/2 a1--------------> is the first term an--------------> is the last term n--------------- > is the number of terms we have that a1------------> 4*(1)+1=5 a30----------> 4*(30)+1=121 n------------- > 30 S30=30*(5 + 121)/2=1890
