1)√(n？ +1) and √(n? +n), when n is large enough, they are all equivalent to n.

Because lim √ (n+1)/n =1= lim √ (n? +n)/n, so when n is large enough √(n? + 1)~√(n？ +n)~n

Sinnπ=0, so whether there is a box or not does not affect the result. Judging from the results, these two limits are really not too big.