time complexity - Big O Notation of an expression -

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if have algorithm takes 4n^2 + 7n moves accomplish, o? o(4n^2)? o(n^2)?

i know 7n cut off, don't know if should keep n^2 coefficient or not.

thanks

you should drop coefficients because question asking "on order of", tries characterize linear, exponential, logarithmic, etc... is, when n large, coefficient of little importance.

this explains why drop +7n, because when n large, term has relatively little significance final answer. if familiar calculus, might lim n->inf(4*n^2+7n) ~= lim n->inf(4*n^2) ~= lim n->inf(n^2)

you can think in graphical sense... is, if graph function 4n^2 + 7n larger , larger values of n, mathematician might "it looks n^2". granted, have liberal mathematician, isn't rigorous statement, that's o(...) trying convey.


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