A (2, 3, -1) B (0, 3, -2) C (5, 7, -4)
2. Дано: a → = (3, -7, 14)
b → = (2, -11, -10)
Найти: a → + b →, 4a → -1/2 b → , a → * b →
Это задачи на векторы.
vector{a}+vector{b}=(3+2;-7+(-11);14+(-10))=(5;-18;4)
4*vector{a}-(1/2)*vector{b}=(4*3-(1/2)*2;4*(-7)-(1/2)*(-11);4*14-(1/2)*(-10))=(11;-45/2;61)
vector{a}*vector{b}=3*2+(-7)*(-11)+14*(-10)=6+77-140=
1.