If $vtimes w = 4i + 7j + 5k$ then what is $vtimes w + wtimes v$?











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If $vtimes w = 4i + 7j + 5k$ then what is $vtimes w + wtimes v$?




$v$ and $w$ are vectors, they aren't given. I have no idea how to do this and apparently it's asked on a quiz as a "surprise" question.






multivariable-calculus vectors 3d







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  • The edited title and question were significantly more readable. When rendered, the command times is displayed as the appropriate cross product symbol. The title is now not very unreadable.
    – Joey Kilpatrick
    22 hours ago

















up vote
-3
down vote

favorite













If $vtimes w = 4i + 7j + 5k$ then what is $vtimes w + wtimes v$?




$v$ and $w$ are vectors, they aren't given. I have no idea how to do this and apparently it's asked on a quiz as a "surprise" question.






multivariable-calculus vectors 3d







share|cite|improve this question









New contributor




ufotink is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















  • The edited title and question were significantly more readable. When rendered, the command times is displayed as the appropriate cross product symbol. The title is now not very unreadable.
    – Joey Kilpatrick
    22 hours ago















up vote
-3
down vote

favorite









up vote
-3
down vote

favorite












If $vtimes w = 4i + 7j + 5k$ then what is $vtimes w + wtimes v$?




$v$ and $w$ are vectors, they aren't given. I have no idea how to do this and apparently it's asked on a quiz as a "surprise" question.






multivariable-calculus vectors 3d







share|cite|improve this question









New contributor




ufotink is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












If $vtimes w = 4i + 7j + 5k$ then what is $vtimes w + wtimes v$?




$v$ and $w$ are vectors, they aren't given. I have no idea how to do this and apparently it's asked on a quiz as a "surprise" question.






multivariable-calculus vectors 3d




multivariable-calculus vectors 3d






share|cite|improve this question









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ufotink is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question









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ufotink is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|cite|improve this question




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edited 21 hours ago









Brahadeesh

5,52941956




5,52941956






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asked 22 hours ago









ufotink

43




43




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ufotink is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






ufotink is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












  • The edited title and question were significantly more readable. When rendered, the command times is displayed as the appropriate cross product symbol. The title is now not very unreadable.
    – Joey Kilpatrick
    22 hours ago




















  • The edited title and question were significantly more readable. When rendered, the command times is displayed as the appropriate cross product symbol. The title is now not very unreadable.
    – Joey Kilpatrick
    22 hours ago


















The edited title and question were significantly more readable. When rendered, the command times is displayed as the appropriate cross product symbol. The title is now not very unreadable.
– Joey Kilpatrick
22 hours ago






The edited title and question were significantly more readable. When rendered, the command times is displayed as the appropriate cross product symbol. The title is now not very unreadable.
– Joey Kilpatrick
22 hours ago












1 Answer
1






active

oldest

votes

















up vote
2
down vote













Note that the cross product is what we call anti-commutative, i.e.



$$(vec{v} times vec{w}) = - (vec{w} times vec{v})$$



I feel like this fact will simplify your work greatly.






share|cite|improve this answer





















  • thanks! I figured it out if I'm correct, the answer would be 0?
    – ufotink
    22 hours ago










  • Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
    – Eevee Trainer
    22 hours ago











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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
2
down vote













Note that the cross product is what we call anti-commutative, i.e.



$$(vec{v} times vec{w}) = - (vec{w} times vec{v})$$



I feel like this fact will simplify your work greatly.






share|cite|improve this answer





















  • thanks! I figured it out if I'm correct, the answer would be 0?
    – ufotink
    22 hours ago










  • Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
    – Eevee Trainer
    22 hours ago















up vote
2
down vote













Note that the cross product is what we call anti-commutative, i.e.



$$(vec{v} times vec{w}) = - (vec{w} times vec{v})$$



I feel like this fact will simplify your work greatly.






share|cite|improve this answer





















  • thanks! I figured it out if I'm correct, the answer would be 0?
    – ufotink
    22 hours ago










  • Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
    – Eevee Trainer
    22 hours ago













up vote
2
down vote










up vote
2
down vote









Note that the cross product is what we call anti-commutative, i.e.



$$(vec{v} times vec{w}) = - (vec{w} times vec{v})$$



I feel like this fact will simplify your work greatly.






share|cite|improve this answer












Note that the cross product is what we call anti-commutative, i.e.



$$(vec{v} times vec{w}) = - (vec{w} times vec{v})$$



I feel like this fact will simplify your work greatly.







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered 22 hours ago









Eevee Trainer

8278




8278












  • thanks! I figured it out if I'm correct, the answer would be 0?
    – ufotink
    22 hours ago










  • Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
    – Eevee Trainer
    22 hours ago


















  • thanks! I figured it out if I'm correct, the answer would be 0?
    – ufotink
    22 hours ago










  • Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
    – Eevee Trainer
    22 hours ago
















thanks! I figured it out if I'm correct, the answer would be 0?
– ufotink
22 hours ago




thanks! I figured it out if I'm correct, the answer would be 0?
– ufotink
22 hours ago












Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
– Eevee Trainer
22 hours ago




Well, the zero vector, $vec{0} = 0hat{i} + 0hat{j} + 0hat{k}$, more appropriately, but yeah you get the idea.
– Eevee Trainer
22 hours ago










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