immediatewrite18{makeindex jobname.nlo -s nomencl.ist -o jobname.nls}
documentclass[12pt]{report}
DeclareMathSizes{12}{30}{16}{12}
usepackage[utf8]{inputenc}
usepackage{lineno}
usepackage{amsmath}
usepackage{array}
usepackage{mathptmx}
begin{document}
begin{equation}
[L_{ss}]=
begin{bmatrix}
 R_s & M_s & M_s \ M_s & R_s & M_s \ M_s & M_s & R_s
end{bmatrix},
[L_{rr}]=
begin{bmatrix}
R_r & M_r & M_r \ M_r & R_r & M_r \ M_r & M_r & R_r
end{bmatrix}
[M_{sr}]=[M_{rs}]^t= M_{sr}
begin{bmatrix}
cos(theta) & cos(theta-4pi/3) & cos(theta-2pi/3) \ cos(theta-2pi/3)
& cos(theta) & cos(theta-4pi/3 \ cos(theta-4pi/3) & cos(theta-2pi/3)
& cos(theta)
end{bmatrix}
end{equation}
end{document}