Hi Anil,
Here an example of a TwoAxisPlot with a simple relation between two functions
Plot[{Sin[x], 3 Sin[x] + 5 Cos[x]}, {x, 0, 4 Pi}];
The TwoAxisPlot, rescales two plots to appear to have the same range. The ranges of the functions are shown on the left and right sides of the frame:
TwoAxisPlot[{f_, g_}, {x_, x1_, x2_}] :=
Module[{fgraph, ggraph, frange, grange, fticks,
gticks}, {fgraph, ggraph} =
MapIndexed[
Plot[#, {x, x1, x2}, Axes -> True,
PlotStyle -> ColorData[1][#2[[1]]]] &, {f, g}]; {frange,
grange} = (PlotRange /. AbsoluteOptions[#, PlotRange])[[
2]] & /@ {fgraph, ggraph}; fticks = N@FindDivisions[frange, 5];
gticks =
Quiet@Transpose@{fticks,
ToString[NumberForm[#, 2], StandardForm] & /@
Rescale[fticks, frange, grange]};
Show[fgraph,
ggraph /.
Graphics[graph_, s___] :>
Graphics[
GeometricTransformation[graph,
RescalingTransform[{{0, 1}, grange}, {{0, 1}, frange}]], s],
Axes -> False, Frame -> True,
FrameStyle -> {ColorData[1] /@ {1, 2}, {Automatic, Automatic}},
FrameTicks -> {{fticks, gticks}, {Automatic, Automatic}}]]
The combined plot illustrates the fact that for some and :
TwoAxisPlot[{Sin[x], 3 Sin[x] + 5 Cos[x]}, {x, 0, 4 Pi}]

I hope this will help. Regards,....Jos
Note: See a further example with the function 'Overlay' on
TwoAxisPlot with 'Overlay'