# Discrete math: Big O and Omega notation help

#### Herondaleheir

##### New member
Determine whether or not the following is true.

a) 5n + 3n log n is Ω(n)

b) log((1/n) + n^2 ) is O(log n)

Can someone teach me step by step how to do these? I'm especially confused with b) because of the O(log n) and would appreciate some help or even a push in the right direction. I'm unconfident with logarithms in general which is why I'm struggling with these two questions in particular.

#### JeffM

##### Elite Member
What definitions are you expected to use for big $$\displaystyle O$$ and big $$\displaystyle \Omega$$?