# Vector space

• Sep 15th 2009, 12:50 AM
roshanhero
Vector space
Find a vector which is orthogonal to P=(1,2,3) with respect to Q=(0,-2,-3) and normalize that vector.
• Sep 15th 2009, 03:53 AM
courteous
What do you mean with "with respect to"? Are you searching vector orthogonal to $\vec{PQ}$?
• Sep 16th 2009, 01:02 AM
roshanhero
No
• Sep 16th 2009, 07:11 AM
HallsofIvy
Then please answer the question. What does " $\vec{u}$ orthogonal to $\vec{v}$ with respect to $\vec{w}$" mean? I know what it means for two vectors to be "orthogonal" but not "with respect to" a third vector. Could you possibly mean "orthogonal to both $\vec{u}$ and $\vec{v}$"? Or are you asking about the "Orthogonal projection of $\vec{v}$ on $\vec{w}$?
• Sep 16th 2009, 07:21 AM
mr fantastic
Quote:

Originally Posted by roshanhero
P=(1,2,3)
Q=(0,-2,-3)

is standard notation for coordinates of points. So what yu have posted is qute ambiguous. Are we meant to assume that P is a vector given by <1, 2, 3> and Q is a vector given by <0, -2, -3>?

Also, I support the several requests for clarification of the question.