Question

Let, a=5i-2j+5k , b=i+4j+6k a)find their cross product (1) b)check,whether they are parellel or not,

Answer 1

Answer:

1)C(-32,-25,28)

2) they are not parallel as they cannot be described as a=kb where k is scalar

Explanation:

for 1)

A(5,-2,5)

B(1,4,6)

cross product= Cx=AyBz-AzBy= -2*6-5*4= -12-20= -32

                         Cy=AzBx-AxBz=5*1-5*6=5-30=-25

                         Cz=AxBy-AyBx=5*4-(-2)*4=20+8=28