how to simplify this equation



0.5*(0.5*(1+n)*cos(a)*cos(b)*sin(a)*sin(b)/(1+n)+0.5*(1+n)^2*(cos(a))^2*(sin(a))^2)+(0.5*%i/sqrt(1+n))*(-(0.5*%i*n/sqrt(1+n))*(cos(a))^2*(cos(b))^2-(0.5*i*n*(1+n)/sqrt(1+n))*(cos(a))^2*(sin(b))^2)+(0.5/(1+n))*(((0.5*(cos(a))^2*(cos(b))^2+0.5*(cos(b))^2*(sin(b))^2+0.5*n^2*(cos(a))^2*(sin(b))^2+0.5*n*(sin(a))^2*(sin(b))^2)/(1+n))+0.5*(1+n)*cos(a)*cos(b)*sin(a)*sin(b))-(0.5*%i/sqrt(1+n))*(0.5*%i*n*sqrt(1+n)*(cos(a))^2*(sin(b))^2+(0.5*%i*n/sqrt(1+n))*(sin(a))^2*(sin*(b))^2)

i got this equation and try to simplify it in maxima

i try used trigsimp command but still couldnt get simplest equation that i
want

hope someone can help me into this. i think the trick should be trigonometry
identity but then when i used trigsimp the equation still not simplify using
trigonometri identity

thanks for looking into this

-- 
Regards,

RAZIF RAZALI,
Tutor & Master Student,
Physics Department,
Faculty Of Science,
Universiti Teknologi Malaysia(UTM).