## AccidentalAiChan 2 years ago Give an example of a situation where finding the cross product of two sets is useful and explain why it is useful. Your example should include two sets and their cross product.

1. itsmylife

if you are talking bout vectors then finding cross product will be helpful when you gotta find the direction of something , coming outta product of two, for example, the cross product of electric current and magnetic field will give you the direction of force :)

2. zzr0ck3r

say you have 15 shirts(set1), and 10 different pairs of pants(set2), and you want to see what every different combination would look like. Then you could take the cross product of those two sets and that would be every possible combination.

3. itsmylife

umm i think thats the combinatorics and i think he's asking bout vector not sure tho

4. zzr0ck3r

5. zzr0ck3r

when we are talking about sets, then the cross product of two sets is every possible combination example A = {1,2} B = {3,4} A X B = {{1,3},{1,4},{2,3},{2,4}}

6. zzr0ck3r

understand @itsmylife ?

7. itsmylife

well it depends how you take the cross product so if i take it as vectors then i dont think your example is suitable

8. zzr0ck3r

9. Erin001001

I'm fairly sure they didn't mean vectors. This has got to be the first time I've heard it called cross product though... Isn't the usual term "Cartesian product"?

10. zzr0ck3r

yes but we call it cross product

11. zzr0ck3r

12. itsmylife

erin i guess if you have studied vectors then you must be familiar with cross and dot products ;) but alright i agree

13. Erin001001

Yes, I am familiar with cross and dot (and direct!) products of vectors :) It is pretty clear what "cross product of sets" means, though it is the first time I've heard the term.

14. zzr0ck3r

yes we know what the inner product(dot product) and outer product(cross product) are in vector language. This is not the same thing. in math we use the same terms over and over. especially for operators. like word "add" does not always mean add like we think it does. we may define the word add to be some other operator.... we simply run out of names:)

15. AccidentalAiChan

Thanks for giving examples :3 I understand it now.