1. AB{9,-10,7} -> (7-(-2)=9, -5-5=-10, 1-(-6)=7)
CB{4,2,-3} -> (7-3=4, -5-(-7)=2, 1-4=-3)
2. |AB|=квадратный корень 9^2 +(-10)^2 + 7^2 = кв.корень 230
3. S={18, -20, 14} - {12,6, -9}
S{6,-26,23} -> ( 18-12=6, -20-6=-26, 14-(-9)+23)
4. Cos(AB, CB)=9*4+(-10)*2+7*(-3)/|AB|*|CB|
Cos(AB, CB) =-5/кв.корень 230*29