Let's start by the radians. Just remember that #360º=2pi#, so whenever is written in function of #pi# follows this proportion; for example, #pi=180º# because it's half that measure and so on.
(I'll adopt three decimals, ok?)
#sin((3pi)/2)=sin((3*180º)/2)=sin(270º)=-0.176#
#cos(-5pi)=cos(-5*180º)=cos(-900º)=cos(-900+360º+360º+360º)=cos(180º)=-0.598#
#(cot(2pi))/3=(cot(360º))/3=(-0,296)/3=0.099#
#tan(8pi)/3=tan(1440)/3=2.238/3=0.746#
Now, the degrees:
#sec(-855º)=sec(-855+360+360+360)=sec(225)=2.722#
#tan(1080º)=-0.856#
#sec(-330º)=sec(-330+360)=6.483#
#csc(945º)=1.722#
Now, let's just substitute them!
#((-0.176+2.722)(-0.598+0.856))/((0.099+6.483)0.746+1.722)#
#(2.546*0.258)/(4.910+1.722)=0.657/6.632=0.099#
Just remembering: I consisdered only three decimal digits, so this answer is not precise.
