f(n) * log2(f(n)c) = O (g(n) * log2g(n))
=> c * f(n) * log2(f(n)) = O (g(n) * log2g(n))
=> f(n) * log2(f(n)) = O (g(n) * log2g(n))
Even we can check if it is always true or not,
A). 1/n2 = O(1/n) --> True in this ( f,g are non decreasing functions, so, i should not include this example, but even if we use , it is true )
B). n = O(n2) --> Even true for this .