Study the graph of exponential and logarithmic functions in base a using this applet

Can you explain why a > 0 and a cannot be equal to 1?[br](Ask your teacher or check on the math experts on the Internet if you still can't figure out)[br][br]Input various values of a eg[br]Case 1 where a > 1, integer values 2, 3, 4, 5 and [br]Case 2 where a> 1, rational values 3/2, 4/3, 5/4, 5/2 etc[br]Case 3 where 0 < a < 1, rational values 1/2, 1/3, 1/4, 1/5, 2/3, 3/4, 4/5 etc