Sample question for practise doubt

Question

Consider the following 2 functions:
f(n)= n3, if 0 ≤ n < 10,000
= n2, otherwise
g(n)= n, if 0 ≤ n < 100
= n2 + 5n, otherwise

 

Which of the following option is correct?
(a) f(n) is O(n3) (b) g(n) is O(n3)
(c) O(f(n)) is same as O(g(n)) (d) g(n) is O(1)

Answer 1

hope it helps...

Comments

How did  You finally determine that  O(f(n)) is same as O(g(n)) ?

 

Please explain

Answer 2

At asymptotical(tend to infinite values) ,let here be for n beyond 10000,(as it is the max number in ques) ,

f(n) = n2 = O(n2)  and g(n) = n2+5n = O(n2)

and n2 can be written as O(n3) hence both opt A and B are correct , still opt C wins the race as it is the EXACT answer as both fn and gn are same in Big-oh.