I have a question in a book I am solving(Discrete Structures by Kolman, Busby & Ross). I am unable to make sense from the question. It is stated below, Show that k is odd is a necessary and sufficient condition for k^3 to be odd.
Now what I extracted out of the question was, As k is odd is necessary as well as sufficient condition for k^3 then they must be the same logic I must say that they are logically equivalent. Is this what the question demands? Please help me understand the question.