scalar triple product, check.

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September 30th 2008, 11:53 PM
Craka

scalar triple product, check.

Could someone please check the answer for this.

Given these vectors
$ \begin{array}{l} \vec u = 2\hat i - \hat j + \hat k \\ \vec v = 3\hat i + \hat j - 2\hat k \\ \vec w = 3\hat i + 2\hat j \\ \end{array} $

Find $\vec u \bullet (\vec v \times \vec w)$

When I calculate this I get 17 however the answer in the text is given as being 14.
Could someone confirm the answer please?
October 1st 2008, 12:32 AM
mr fantastic

Quote:

Originally Posted by Craka

Could someone please check the answer for this.

Given these vectors
$ \begin{array}{l} \vec u = 2\hat i - \hat j + \hat k \\ \vec v = 3\hat i + \hat j - 2\hat k \\ \vec w = 3\hat i + 2\hat j \\ \end{array} $

Find $\vec u \bullet (\vec v \times \vec w)$

When I calculate this I get 17 however the answer in the text is given as being 14.
Could someone confirm the answer please?

I get 17 too. Perhaps we're both making the same mistake ..... (Rofl)
October 1st 2008, 01:02 AM
Craka

Cheers. Glad to know I don't make mistakes all the time