Talk:Vertex angle

A few days ago, I created the article titled polar sine, that begins thus:
 * In mathematics, the polar sine of a vertex angle of a polytope is defined as follows. Let v1, ..., vn, n ≥ 2, be non-zero vectors from the vertex in the directions of the edges.  The polar sine of the vertex angle is
 * $$ \operatorname{psin}(v_1,\dots,v_2) = \frac{\operatorname{volume}(v_1,\dots,v_n)}{\|v_1\|\cdots\|v_n\|}, $$
 * the volume in the numerator being that of the parallelotope whose edges at the vertex in question are the given vectors v1, ..., vn.
 * $$ \operatorname{psin}(v_1,\dots,v_2) = \frac{\operatorname{volume}(v_1,\dots,v_n)}{\|v_1\|\cdots\|v_n\|}, $$
 * the volume in the numerator being that of the parallelotope whose edges at the vertex in question are the given vectors v1, ..., vn.
 * the volume in the numerator being that of the parallelotope whose edges at the vertex in question are the given vectors v1, ..., vn.

...with a then-red link to vertex angle. I don't think that topic is addressed in this new article titled vertex angle. Michael Hardy (talk) 18:52, 2 May 2008 (UTC)