Hello I am a university student working my way through a computer science degree but halfway I gave up my studies to focus on personal problems and now that I am back I struggle even with basic things because I lost touch with the basics for a long period of time and now that I am back to studying I am having a  hard time continuing from where I left of and I feel so helpless and embarrassed when I find myself stuck to something so simple, if someone can explain to me the steps that took place and maybe have some recommendation how to refresh the basics or have a reference somewhere that I can lookup basic knowledge to understand the steps in a solution, that would be really helpful, thank you.

n(n+1)(2n+1)+6(n+1)\^2=

=(n+1)$n(2n+1)+6(n+1)$
The factor n+1 appears in each of the summands, so we can factor it out. That is, using the distributive law we can rewrite the expression as the right hand side of the equation.
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