Question

if A=i+2j-2k,B=3i+mj-6k are two parallel vector then the value of m is​

Answer 1

Answer:

Therefore you have

v1→=2i^+3j^−k^

v2→=4i^+6j^+xk^

Now v1→ is parallel to v2→ implies

v1→=kv2→ where k is a scale factor.

therefore we have

2=4k

3=6k

−1=xk

From the first two equations we have

k=0.5

substituting into the third equation we have

−1=0.5x which then gives x=−2

Answer 2

Answer:

For two vectors to be perpendicular-

a.b=0

⟹(2i+mj−3k).(i−2j+k)=0

⟹2−2m−3=0

⟹m=

2

−1