[(√n^2-1)+(√n^2-4)+(√n^2-9)+……(√n^2-(n-1)^2)]/n^2

[(√n^2-1)+(√n^2-4)+(√n^2-9)+……(√n^2-(n-1)^2)]/n^2
求它的极限.
是根号下 n^2-1，n^2-4 这种式子的整体。n→+无穷大