limn→∞=3((n+1)!)(n−1)3n+(n!)n2
I'm stuck with this limit. I managed to rewrite it to the following form: 3n−33n(n+1)!+n2(n+1)
but I don't know how to further simplify it. To me it seems like this goes to 0 because 3n grows faster than any other term in the function, but wolfram alpha tells me it's 3.
Answer
Divide the top and bottom by n!:
limn→∞3((n+1)!)(n−1)3n+(n!)n2=limn→∞3(n+1)(n−1)3nn!+n2=limn→∞3n2−3n2=limn→∞3−3n2=3
The thing is that n! grows way faster than 3n once n>3.
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