https://www.chegg.com/homework-help/questions-and-answers/10-points-2-points-t-f-8-points-justification-3-assume-functions-t-s-t-n-o-s-n--following--q40020288

https://www.chegg.com/homework-help/questions-and-answers/10-points-4-one-obtain-asymptotically-tight-bound-directly-computing-limit-n-goes-infinity-q40020290