Find the unit vector perpendicular to a and b

[anantchowdhary]

Homework Statement

there are two vectors a and b

a=3i+2j+k
b=2i+j+2k

Find the unit vector perpendicular to a and b

Homework Equations

| A|^a=A

The Attempt at a Solution

I don't kno how to start

 

[neurocomp2003]

go to mathworld.com and find what it means to be a perpendicular vector to
2 other vectors.

 

[cristo]

Well, calling the third vector c=(l,m,n), you should be able to find 3 equations. They will come from the facts that (i) a is perpendicular to c, (ii) b is perpendicular to c, and (iii) c is a unit vector.

 

[anantchowdhary]

i tried to use the dot product and cross product but i still couldn't get the answer

 

[cristo]

Well what did you try?

 

[malawi_glenn]

Homework Statement

there are two vectors a and b

a=3i+2j+k
b=2i+j+2k

Find the unit vector perpendicular to a and b

Homework Equations

| A|^a=A

The Attempt at a Solution

I don't kno how to start

Do you know the properties of vector (cross) product ?
and this is precalculus math, not physics

 

[genius_me]

try using crossproduct,

a x b = resultant(r)
divide a x b by the magnitude of r,
u will get ur unit vector

 

[krateesh]

ya axb..will give us vector whose unit vector is required

 

[anantchowdhary]

yea..thnx...gt the answer long ago! thnx nywyz

help much appreciated