Math Is Fun Forum

samuel12

Member

Registered: 2010-07-17

Posts: 19

Big O notation

Hey guys just need some help with this one, thanks.

(a) If

and

show that

mathsyperson

Moderator

Registered: 2005-06-22

Posts: 4,900

Re: Big O notation

Maybe I'm missing something, but can't you disprove that with, for example, D_1(N) = -D_2(N)?

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Why did the vector cross the road?
It wanted to be normal.

samuel12

Member

Registered: 2010-07-17

Posts: 19

Re: Big O notation

Hi mathsyperson, I'm just as confused as you are
An example of one we did in class is :

Show that

is

for

and find

  since log is increasing

So if someone could maybe go through this one, it would be much appreciated, cheers=)

Find

And maybe even (if you're feeling lucky )

Let f(n) = n^2 and g(n) = 2n^2. Find O(g(n)-f(n))

Thanks for your time