I have a huge expression that makes use of Mathematica's units support (Quantity[]) that I know evaluates to a dimensionless quantity. However, I'm unable to get Simplify[] nor UnitSimplify[] to simplify the expression to something not containing units.
Because the actual expression I'm trying to simplify is far too huge to include here, I've made a small example that reproduces this problem:
Quantity[a, "Ohms"] / (b Quantity[1. c, "Ohms"] + Quantity[d, "Ohms"])Note the presence of variables, some within a Quantity[] and some outside, as well as a machine-precision number.
But clearly the "Ohms" unit is a common factor in both the numerator and denominator, so it can be cancelled away.
How can I get Mathematica to simplify this down to:
a / (1. b c + d)Note: I'm using Mathematica 12.0
Edit: Additional test case that includes slightly more of the original expression
Quantity[a, "Ohms"] / (Tanh@Sqrt[b] Quantity[1. c, "Ohms"] + Quantity[d, "Ohms"])