3 marks Using the definition of Big-Oh, prove that 2n2(n - 1) is not O(n2). 6 marks] Let f(n), g(n), h(n) be complexity functions. Using the definition of Big-Oh, prove following two claims: a) [3 marks] Let k be a positive real constant and f(n) is 0(g(n)), then k . f(n) is O(g(n)). b) 3 marks] If f(n) is O(g(n)) and g(n) is O(h(n)), then f (n) is O(h(n). the