1. The problem statement, all variables and given/known data Prove the following: xn-yn= (x-y)(xn-1+xn-2y+ … + xyn-2+yn-1) 3. The attempt at a solution What do the 3 full stops (...) mean? I didnt know where to start, so I tried to subsitute a number for n, I said n=5, I then multiplied out the brackets and removed terms that were cancelled out through opposite signs. This leaves me with: = x5+x2y3-x3y2-y5 and from there I am stuck. extra - ANY ADVICE? I am from the UK, I have finished my undergraduate degree in Ocean Science where we used equations but did not have to derive them and am looking to take a masters in physical oceanography. I have not studied maths since GCSE, and to do the masters I need to know calculus and physics. I looked into taking courses but could not find any suitable for me to do within a few months. I have University Calculus (Hass,Weir & Thomas) and University Physics (Young and Freedman) which were bought for me by my professor who has encouraged me to improve my maths and physics because he thinks I am capable of doing well in physical oceanography. In addition I have bought Spivaks Calculus book after reading the reviews online and have just started with the 1st chapter. Does anyone have any advice for me as I am starting out? Thanks!