reposition interact slider and avoid division by zero

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Can I reposition the interact slider for a plot? It often goes above the viewport and if I scroll the viewport to see the slider I cut off the lower part of the function.

Also, some plots, at a certain point, end up with division by zero. I get an error message at that point in the slider, but you can slide past that. Still, is there a way to avoid the one point where I divide by zero in a plotting statement? I tried "assume" but I apparently don't quite know how it works and the docs I found so far are inscrutable.