Your first decision is whether or not the italics need to be retained in the braille copy. Is "x-axis" always italicized? If so, you can ignore the typeface according to Section 34a.
If it is determined that the italic typeface has mathematical significance and must be retained, then the last sentence of Section 32d applies. The type-form indicator is effective for the entire compound expression.
Section 33b applies to phrases, so does not apply here. Reminder: The BANA Update includes some format changes to the examples in Section 33, as well as changed text for Section 33b, with five additional examples.
Lindy Walton (Committee Member)