not sure of solution method

[Otis]

i did read the guidelines.Okay ...

Okay! But, the guidelines aren't there just for the reading. It's our hope that students follow them. That is, if you didn't understand symbol n, then that's what you ought to have asked about up front. Cheers.

... If you cannot begin an exercise, please tell us why (eg: unknown concept, confusing example, unfamiliar symbol, missing definition, unclear language) ...

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