|vector{AB}|=sqrt((3/4)^2+(-1/2)^2+1^2)=sqrt(29)/4
vector{AC}={0-(1/4);-1-1;3-2}={-1/4;-2;1}
|vector{AC}|=sqrt((-1/4)^2+(-2)^2+1^2)=9/4=2,25
vector{BC}={0-1);-1-1/2;3-3}={-1;-3/2;0}
|vector{BC}|=sqrt((-1)^2+(-3/2)^2+0^2)=sqrt(13)/2
Р(Δ АВС)=(sqrt(29)/4)+2,25+(sqrt(13)/2)=
=(sqrt(29)+9+2sqrt(13))/4
vector{a}+vector{b}={3+(-2);2+3;1+1}={1;5;2}
|vector{a}+vector{b}|=sqrt(1^2+5^2+2^2)=sqrt(30)
|vector{a}|=sqrt(3^2+(-2)^2+1^2)=sqrt(14)
|vector{b}|=sqrt((-2)^2+3^2+1^2)=sqrt(14)
|vector{a}|-|vector{b}|=0
vector{2a}-vector{3c}={2*3-3*(-3);2*(-2)-3*2;2*1-3*1}=
={15;-10;-1}
|vector{2a}-vector{3c}|=sqrt(15^2+(-10)^2+(-1)^2)=sqrt(326)