If Sn = 2n ^ 2 + 3n-4, then an=____

n>=2
S(n-1)=2(n-1)^2-3(n-1)-5
=2n^2-7n
an=Sn-S(n-1)=10n-4
a1=S1=2+3-4=1
An = 10n-4 when n > = 2 is not met
therefore
an=
1,n=1
10n-4,n≥2

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