# Vector Products

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1. Hi Everyone,

Quick question regarding vector cross products.

Im looking at the question:

The vector a points east with magnitude 2, and the b points north-west with magnitude 3. Wha is the magnitude and direction of c = a x b?

Now the mangitude was easy to calculate, 3*(2^1/2). However im having trouble with the direction.

We've been taught the right hand rule, but does that only work if vectors a and b are perpendicular and your in a 3D coordinate system?

The answer is 'points up'... very specific, so im guess that means north?

Or would you in a case like this when a and b are not perpendicular would you use geometry to calculate which direction the cross product would be in?

Cheers for any help guys

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