Справка LibreOffice 7.5

Returns the sine of a complex number. The sine of a complex number can be expressed by:

МНИМ.SIN(КомплексноеЧисло)

Complex_number is a complex number whose sine needs to be calculated.

=МНИМ.SIN("4-3i")

возвращает -7,61923172032141+6,548120040911i.

=IMSIN(2)

returns 0.909297426825682 as a string. The imaginary part is equal to zero, so it is not displayed in the result.