I have a function:

```
you[r_] : = 1/2 * (uj + u∞) -
1/2 * (uj - u∞) * Tanh[1/4*Rθ*(r/R - R/r)]
```

Where:

```
uj = 1;
u∞ = 0;
R = 1;
```

I want to trace:

```
Plot[(u[r/R] - u∞) / (uj - u∞), {r, 0, 3},
PlotRange -> All]
```

But for three different values of parameters `Rθ`

, something like that:

```
Plot[(u[r/R] - u∞) / (uj - u∞), {r, 0, 3},
PlotRange -> All]/. {Rθ-> 10, Rθ-> 5, Rθ-> 2.5}
```

How to do that?