This question is taken from one of the PJC revision sets. The origin of this question is unknown.
The prove by mathematical induction part is easy and therefore I go straight to the hence parts. The hence parts requires the use of method of difference, summation and limits for infinite series.
For best results, pause the video in the beginning and attempt the question by yourself before viewing the solution.
To view the boardcast on YouTube, please click on the YouTube icon at the lower right hand corner or click here.