I believe there is a typo in this sentence from a book. Can someeone confirm it?

"Since a.b is a scaler then (a.b)xc has no meaning and a.(bxc) may be wriiten as a.bxc without ambiguity."

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- Mar 30th 2012, 02:13 AMStuck Manscalar product and vector product combined
I believe there is a typo in this sentence from a book. Can someeone confirm it?

"Since a.b is a scaler then (a.b)xc has no meaning and a.(bxc) may be wriiten as a.bxc without ambiguity." - Mar 30th 2012, 02:36 AMPlatoRe: scalar product and vector product combined
- Mar 30th 2012, 02:58 AMStuck ManRe: scalar product and vector product combined
Why do the brackets say nothing? I find it extremely unusual that brackets are not observed. This is not what I find with a Casio calculator.

- Mar 30th 2012, 03:09 AMPlatoRe: scalar product and vector product combined
I have no idea what "Why do the brackets say nothing?" could mean.

These are vectors. $\displaystyle A\cdot B$ is a scalar, a number.

Cross products are vectors. If $\displaystyle t$ is a scalar and $\displaystyle C$ is a vector then $\displaystyle t\times C$ is meaningless.

A calculator has absolutely nothing to do with vectors. - Mar 30th 2012, 03:21 AMStuck ManRe: scalar product and vector product combined
I thought that t x C was multiplying the vector C by a scaler. It is not the same as tC then? My fx-991 does have a vector mode. I'm not sure now if it does vector products.

- Mar 30th 2012, 03:29 AMStuck ManRe: scalar product and vector product combined
My calculator does not follow what is being said in that quote from the book. It can do vector products with AxB or AB or A(B).

- Mar 30th 2012, 03:42 AMPlatoRe: scalar product and vector product combined
- Mar 30th 2012, 08:09 AMHallsofIvyRe: scalar product and vector product combined
- Mar 30th 2012, 08:11 AMHallsofIvyRe: scalar product and vector product combined
Taking Plato's example of A= <1, 2, 3> and B= <3, 2, 1>, what does your calculator give for AB or A(B)? There are

**two**kinds of "vector times vector" product (well, three if you include the "exterior product- the exterior product of two n dimension vectors is a n by n tensor.) so the notation "AB" or A(B) is ambiguous. - Mar 30th 2012, 10:32 AMStuck ManRe: scalar product and vector product combined
I get the vector product, -4i, 8j, -4k for AB, A(B) and AxB with the calculator.

I have noticed that with the calculator the scaler product has higher precedence than the vector product which has been confusing me. The vector product has precedence in mathematics. I feel that Casio should fix this with later models. - Mar 30th 2012, 11:11 AMPlatoRe: scalar product and vector product combined
You are not using that calculator correctly.

Look at this web page.

Look at the dot product. - Mar 30th 2012, 11:32 AMStuck ManRe: scalar product and vector product combined
I am. HallsOfIvy copied B wrongly and I used it. I am still questioning why the calculator puts the dot product above the vector product.

- Mar 30th 2012, 01:17 PMHallsofIvyRe: scalar product and vector product combined
Once again, if you do the dot product first, you do NOT have two vectors and cannot do the cross product.