Consider the logarithmic function y=logax, where a>0 and a=1.
a. (i) State the domain and range of the function when a>1.
b. (ii) Prove that the curve approaches the y-axis but never meets it, and hence obtain the equation of its vertical asymptote.
c. (iii) Determine, with reasons, whether the curve is increasing or decreasing when (a) a>1, (b) 0<a<1.
d. (iv) On the same set of axes, sketch the graphs of y=log2x and y=log1/3x, clearly labelling their common asymptote and the point through which both curves pass.