The graph of #y = log_("1/a")x# is the same as the graph of? 1. #y = -a^x# 2. #y = log_ax# 3. #y = (1/a)^x# 4. #y = -log_ax# 5. #y = log_a(-x)#

Answer is 4. #y = -log_ax#.

Thanks in advance