函数f(x)=x^2+ax+3对称轴x=-a/2,依题意得①当-a/2≤-2时,当x∈[-2,2]时,f(x)最小值≥a即:f(-2)=4-2a+3≥a,无解②当-2<-a/2<2,当x∈[-2,2]时,f(x)最小值≥a即:f(-a/2)≥a,得-4<a≤2③当-a/2≥2时,当x∈[-2,2]时,f(x)最小值≥a即:f(2)=4+2a+3≥a,得-7≤a≤-4综上所述得:-7≤a≤2