# Cannot plot two graphics together

I am trying to plot these graphics together. I tried with Plot and Show command but it doesn't work. Please help!

sol2 = NDSolve[{0.0099 u'[t] == v[t] - u[t]*v[t] + u[t] - 2 u[t]^2,
2.4892*10^(-5)*v'[t] == -v[t] - (u[t])*v[t] + 0.45*3, u[0] == 0.1,
v[0] == 0.2}, {u[t], v[t]}, {t, 0, 50}]
q1 = Plot[u[t] /. sol2, {t, 0, 1}, PlotStyle -> Red]
q2 = Plot[v[t] /. sol2, {t, 0, 1}, PlotStyle -> Blue]
Show[{q1, q2}]

• It is actually working, the only issue is that the plot range for the Show command comes from the first plot. If you use Show[q1, q2, PlotRange -> {0.68, 0.81}] you should see both plots. However, they look like flat lines because the plot ranges are so different (look at the y-axis of the plots for q1 and q2). – MassDefect Nov 24 '19 at 19:34
• Thanks! Actually they are not so different - they are in the range (0.6,0.8). I cannot understand why the graphs are straight lines. – Ксения Цочева Nov 24 '19 at 20:02
• Look closely at the plot ranges of the individual plots. – Bob Hanlon Nov 24 '19 at 20:17
• The height of each graph is like 0.00001. When you scale the graph to show from 0.6 to 0.8, the height of each curve becomes very very small. – MassDefect Nov 25 '19 at 3:09

There is not a one-size-fit-all solution for this, I think.

If you are more interested in comparing those functions on the same scale:

q1 = Plot[u[t] /. sol2, {t, 0, 1}, PlotStyle -> Red, PlotRange -> All];
q2 = Plot[v[t] /. sol2, {t, 0, 1}, PlotStyle -> Blue,
PlotRange -> All];
Show[{q1, q2}, PlotRange -> Full, ImageSize -> Scaled[0.6]]


If you are interested in fine structure of those functions then this representation should be more helpful:

q1 = Plot[
u[t] /. sol2, {t, 0, 1}
, PlotStyle -> Red
, ImagePadding -> {{45, 45}, {20, 0}}
, Frame -> {True, True, True, False}
, FrameStyle -> {Automatic, Red, Automatic, Automatic}
, ImageSize -> Scaled[0.6]
];
q2 = Plot[
v[t] /. sol2, {t, 0, 1}
, PlotStyle -> Blue
, ImagePadding -> {{45, 45}, {20, 0}}
, Frame -> {False, False, False, True}
, FrameTicks -> {{None, All}, {None, None}}
, FrameStyle -> {Automatic, Automatic, Automatic, Blue}
, ImageSize -> Scaled[0.6]
];
Overlay[{q1, q2}]