Adding a symbol to eqn

[Robert Goulding]

I'm sure this is very easy, but I'm rusty on groff fonts, and I'm not sure
how to do it. I want to add the triangle symbol △ (U25b3) as an operator to
eqn. So, this is my document:

.EQ
delim $$
define triangle 'type "operator" △'
.EN
.LP
In $triangle ABC$ there are three sides.



When I run this through groff -ps -e -ms -k I get the message:

warning: can't find special character 'u25B3'

which I was kind of expecting. But is there any easy way to point
grops towards the definition of U25B3?

Robert.

Robert Goulding
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