DOES THE SEQUENCE CONVERGE OR DIVERGE? 7n! ---- 3^n
As n-> infinity
diverge
as n -> infinity, the sequence converge only when it reachs 0, diverge when it goes infinity
?
diverges because the limit as n goes to infinity is infinite you can prove that \(n!> 3^n\) for \(n>6\) or \(n>7\) one of those two
How to simplify the fraction though to show this? That factorial is really throwing me off
As satellite73 showed, n!>3n for n>7. For example, 3^7 = 2187 and 7! = 5040 From n = 7, if we increase n by 1 3^n increase 3 times but n! increase 8, 9, 10... times. Thus n! is much greater than 3^n as n -> infinity. There is no way to simply n! and 3^n. However, we can use the rule when n -> infinity. If the numerator increases faster than the denominator, the fraction approaches infinity. On the other hand, if the numerator increases slower than the denominator, the fraction approaches 0.
By the way, satellite included the coefficient 7, so his prove only needs n = 6. I ignored the coefficient 7, so I started n =7. In both cases, the sequence approaches infinity.
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