Cross Product Continuity: Showing Definition is Satisfied

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1. Show that the cross product is a continuous function

3.
I have tried to apply the definition of continuity: find a delta such that
|x-y|< delta implies |f(x)-f(y)|< epsilon
but I'm having trouble finding a delta that would take me to the conclusion.
 
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Perhaps you should show us what you've tried. What is |f(x)-f(y)| in this case?
 
In this case, |f(x)-f(y)| is a real number (the length of a vector in R^3).
A better question is what is |x-y|. x is one pair of vectors in R^3 and y is another pair of vectors in R^3. Then what is |x-y|?
I have tried relating |x-y| to the fact that |a x b|=|a||b|sin(theta) but can't get anything that seems to be on the right direction.
 
I figured it out.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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