Remove special character in cos() and sin()

appj.adoc

@@ -67,11 +67,11 @@ Note that, for simplicity of notation, the descriptions of the interpolation met
 |=============== 
 | |Description | Formula 
 
-| `fll2v` | Conversion from geocentric `(latitude, longitude)` to three-dimensional cartesian vector `(x, y, z)` | `(x, y, z) = fll2v(ll) = (cos⁡(ll.lat)*cos⁡(ll.lon), cos⁡(ll.lat)*sin⁡(ll.lon), sin⁡(ll.lat))` +
+| `fll2v` | Conversion from geocentric `(latitude, longitude)` to three-dimensional cartesian vector `(x, y, z)` | `(x, y, z) = fll2v(ll) = (cos(ll.lat)*cos(ll.lon), cos(ll.lat)*sin(ll.lon), sin(ll.lat))` +
 
 | `fv2ll` | Conversion from three-dimensional cartesian vector `(x, y, z)` to geocentric `(latitude, longitude)`| `(lat, lon) = fv2ll(v) = (atan2(v.y, v.x), atan2(z, sqrt(v.x * v.x + v.y * v.y))` +
 
-| `faz2v` | Conversion from `(azimuth, zenith)` angles to three-dimensional cartesian vector `(x, y, z)` | `(x, y, z) = faz2v(az) = (sin⁡(az.zenith) * sin⁡(az.azimuth), sin⁡(az.zenith) * cos⁡(az.azimuth), cos⁡(az.zenith))` +
+| `faz2v` | Conversion from `(azimuth, zenith)` angles to three-dimensional cartesian vector `(x, y, z)` | `(x, y, z) = faz2v(az) = (sin(az.zenith) * sin(az.azimuth), sin(az.zenith) * cos(az.azimuth), cos(az.zenith))` +
 
 | `fv2az` | Conversion from three-dimensional cartesian vector `(x, y, z)` to `(azimuth, zenith)` angles | `(azimuth, zenith) = fv2az(v) = (atan2(y, x), atan2(sqrt(x * x + y * y), z)` +