Verifying Vector Formula: A.B = B.A | Simple Homework Solution

Thread starter BillMath
Start date Oct 4, 2009

AI Thread Summary

The discussion focuses on verifying the vector formula A.B = B.A, which pertains to the scalar product of vectors A and B. The formula is confirmed through the relationship A.B = ABcos(x) and B.A = BAcos(x), highlighting that both expressions yield the same result. It emphasizes that since arithmetic multiplication is commutative, AB equals BA. Thus, the formula holds true for the scalar product of vectors. The conclusion reinforces the correctness of the vector equality based on these mathematical principles.

Oct 4, 2009

BillMath

Homework Statement

Hi all my new friends..
A and B are vectors, A.B = B.A

Homework Equations

The Attempt at a Solution

How we can veryfy that this formula is correct?

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Oct 4, 2009

Vykan12

I'm assuming you mean a scalar product.

A.B = ABcos(x)
B.A = BAcos(x)

AB = BA since arithmetic multiplication is commutative.

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