1. The problem asks when the graph of an exponential function is decreasing or falling. 2. Recall that an exponential function has the form $$y = a^x$$ where $$a$$ is the base and $$a > 0$$. 3. The behavior depends on the base $$a$$: - If $$a > 1$$, the function is increasing because as $$x$$ increases, $$a^x$$ grows larger. - If $$a = 1$$, the function is constant because $$1^x = 1$$ for all $$x$$. - If $$a = 0$$, the function is not defined for all $$x$$ (usually only defined at $$x=0$$), so it does not form a typical exponential graph. - If $$0 < a < 1$$, the function is decreasing because as $$x$$ increases, $$a^x$$ gets smaller. 4. Therefore, the exponential function is decreasing or falling if the base is greater than 0 but less than 1. Final answer: The graph of an exponential function is decreasing when $$0 < a < 1$$.