Incorrect. If you add a positive constant c to the input of a function, that will have the effect of shifting the graph of the original function to the left by c units. If you subtract a positive constant c from the input of a function, that will have the effect of shifting the graph of the original function to the right by c units. For each of these functions, start with the graph of sine or cosine. Shift it left or right according to these rules and see if the new graph matches up with the graph of sine or cosine.