## Cross Product

What is the cross product of a constant and a vector? I know that the cross product between two vectors is the area of the parallelogram those two vectors form. My intuition tells me that since a constant is not a vector, it would only be multiplying with a vector when in a cross product with one. Since the vector will only grow larger in magnitude, there would be zero area in the paralleogram formed because there is no paralleogram.

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The cross product is only defined between vectors of $\mathbb{R}^3$. The cross of a constant and a vector is not defined.

 Quote by Lame Joke "What do you get when you cross a mountain-climber with a mosquito?" "Nothing: you can't cross a scaler with a vector"

 So if I had an equation that contains a term that has a cross product of a constant and a vector, do I just cross it out of the equation? ( it is in an adding term so crossing it out would be okay). That's an awesome joke(:

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## Cross Product

 Quote by quantumfoam So if I had an equation that contains a term that has a cross product of a constant and a vector, do I just cross it out of the equation? ( it is in an adding term so crossing it out would be okay). That's an awesome joke(:
Can you give a specific example?

 Sure! An equation like F=π[hXh+cXh] where h is a vector and c is a constant.

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 Quote by quantumfoam Sure! An equation like π[hXh+cXh] where h is a vector and c is a constant.
That doesn't really make any sense.

 F is a vector.
 Would the term containing the cross product of the constant c and vector h in the above equation just be zero? Or am I able to take cross it out of the above equation?

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 Quote by quantumfoam Would the term containing the cross product of the constant c and vector h in the above equation just be zero? Or am I able to take cross it out of the above equation?
No. As it stands, your equation makes no sense. You can't take the cross product of a scalar and a vector.

 Damn that stinks. Even if the c was a constant?

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 Quote by quantumfoam Damn that stinks. Even if the c was a constant?
Does this equation appear in some book or anything? Can you provide some more context?

 Well I made it up haha. Im sorry. I'm new at this. Do you think you can make an equation that makes sense? Like the one I attempted but failed at.

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