f(n) = omega (n) which means f(n) >=n [ f(n) should be either n or more than n ] ['n' , 'n+1' , 'n+2'......]
g(n) = O(n) which means g(n) <=n [ g(n) should be either n or less than n ] [ '1' , '2' , '3' ........ 'n']
h(n) = which means h(n) = n [h(n) and n both are equal] ['n']
since f(n) + g(n) >= n
therefore f(n) + g(n) = omega(n)