# Manipulate dummy variable after solving trig

Hi! This might be somewhat basic, but is there a way to directly reference the dummy variable that pops up, when solving trigonometric functions?

```
sy(t)=sin(t)/2+7*sin(t/3)/2
sols=solve(sy(t)==0,t, to_poly_solve='force')
sols[0]
```

returns:

```
t == 3*pi + 6*pi*z27541
```

This dummy variable obviously changes every time the command is run, so there is no way of directly referencing it without changing the reference every time. Obviously this doesn't work:

```
sols[0](z=0)
```

The closest I have come, is just blindly referencing the variable which works if there are no other variables in the right hand side, like this:

```
sols[0].rhs()(0)
```

but this gives the obnoxious error message, that "*Substitution using function-call syntax and unnamed arguments is deprecated (...)*"

Is there a way to cleanly tell sage to evaluate an expression, when all z variables are 0 or 1 etc?