2cos37cos23-sin76=2*(1/2)*(cos(37-23)+cos(37+23))-sin76=
=cos14+cos60-sin76=cos14-sin76+1/2=cos14-sin(90-14)+1/2=cos14-cos14+1/2=1/2
d=0,25, C = 3*0,25 = 0,75 м ~ 1 м
d=0,6, C = 3*0,6 = 1,8 м ~ 2 м