\(\vec{\vec{F1}=100\ i\ -120\ j\ +75\ k}\)
\(\vec{F2=\ -200\ i\ +250\ j\ +\ 100\ k}\)
\(\vec{Mo=\ \vec{r}}\ x\ \vec{f}\)
\(\vec{\vec{r1}=0\ i+\ 0j\ +\ 0k}\)
\(\vec{r2=4i\ +\ 5j\ -3k}\)
fr= -100 i + 130j +175k
\(\vec{r}A=0\ i+0j\ +0k\)
\(\vec{rB}\ =4i\ +\ 5j+\ 3k\)
rA x f1 = i j k
0 0 0 = 0 i + 0j+ 0k
100 120 75
RB X F2 i j k
4 5 3 =i(875-390)-j(700-(-300))+k (500 + 520)
-100 130 175 = 485 i -1000j + 1020k