I'm told to prove or disprove that 4√n grows faster than √4n
As n tends to infinity.
From my Previous years Calculus I know that if I take the derivative of two functions, and one is bigger, than it must grow faster.
f(n)=4√n
g(n)=√4n
if
f′(n) is > g′(n) Then f(n) grows faster than g(n), as n→∞
My Attempt:
f′(n)=(ln(4)×4√n))/2√n
g′(n)=(ln(4)×4n/2)/2
But Now I'm not sure if f(n) does grow faster, how would I know that it's first derivative is bigger here, just by plugging in numbers?
Answer
Hint: Look at the ratio 4√n√4n. This is equal to
(44√n/2)√n.
No comments:
Post a Comment