seldutsinso lujvo

s2 is the angle/arccosine of cosine s1.

Cf. sinso, tanjo, dutsinso, selsinso, seltanjo.


In notes:

dutsinso
x1 is the trigonometric cosine of angle/arccosine x2.
selsinso
s2 is the angle/arcsine of sine s1.
seltanjo
t2 is the angle/arctangent of tangent t1.