Mastering Cross and Dot Products for Test Review

Thread starter 1man
Start date Apr 21, 2010
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Cross Cross product Dot Dot product Product

AI Thread Summary

To calculate the cross product of (2A)x(3B), first determine the individual vectors A and B, then apply the scalar multiplication before using the standard cross product formula. For finding the angle theta between two vectors given their components, use the dot product formula and the magnitudes of the vectors. The dot product of 2A and 3B is calculated as 2A · 3B, which can be simplified to 6(A · B). The vectors (2A) and (3B) are normal vectors, confirming that the cross product can be computed. Understanding these concepts is essential for mastering vector operations in preparation for the test.

Apr 21, 2010

1man

i'm reviewing for a test and I can't remember how to do the cross product of (2A)x(3B)
or how to find the angle theta when given components. or dot product: 2A . 3B

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Apr 21, 2010

willem2

Are (2A) and (3B) normal vectors? If so, the link in your own post will tell you
how to do a cross product. If not, what are they?

Apr 21, 2010

1man

they are and i already know
Rz=Az+Bz
Ry=Ay+By
Rz=Az+Bz

but I am not sure how to do (2A)x(3C)

Apr 21, 2010

1man

or (2A)x(3B)

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