- #1
clementc
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Hey guys, I'm a kinda noobie to this site so I have not much experience with the formatting and stuff here, but anyway was doing some physics and came stuck =P Would really appreciate any help
Vectors A and B are drawn from a common point, with the angle in between them [tex]\theta[/tex].
(a) What is the value of [tex] A \times (B \times A)[/tex]?
Now consider any three vectors A, B and C:
(b) Prove that: [tex] A \times ( B \times C) = B( A \cdot C) - C( A \cdot B)[/tex]
(c) Are the two products [tex] A \times ( B \times C)[/tex] and [tex]( A \times B) \times C[/tex] equal in either magnitude or direction? Prove your answer.
I think you would need to use
[tex]A \cdot B = \left|A\right| \left|B\right| \cos \theta [/tex]
and that the magnitude of [tex]A \times B[/tex] is [tex]\left|A\right| \left|B\right| \sin \theta [/tex]
and the right hand rule of course
I don't know =( I can do every question on this problem set except these parts
pleasepleaseplease help
Homework Statement
Vectors A and B are drawn from a common point, with the angle in between them [tex]\theta[/tex].
(a) What is the value of [tex] A \times (B \times A)[/tex]?
Now consider any three vectors A, B and C:
(b) Prove that: [tex] A \times ( B \times C) = B( A \cdot C) - C( A \cdot B)[/tex]
(c) Are the two products [tex] A \times ( B \times C)[/tex] and [tex]( A \times B) \times C[/tex] equal in either magnitude or direction? Prove your answer.
Homework Equations
I think you would need to use
[tex]A \cdot B = \left|A\right| \left|B\right| \cos \theta [/tex]
and that the magnitude of [tex]A \times B[/tex] is [tex]\left|A\right| \left|B\right| \sin \theta [/tex]
and the right hand rule of course
The Attempt at a Solution
I don't know =( I can do every question on this problem set except these parts
pleasepleaseplease help