Is there a vector proof for (u x (v+w)) . r = (u . w)(v . r) - (u . v)(w . r)?

In summary, the problem is to show that (u x (v+w)) dot r equals (u dot w)(v dot r) minus (u dot v)(w dot r). The left-hand side has been simplified to (r x u) dot v plus (r x u) dot w, but it is uncertain if the problem can be solved using only vector identities and without having to prove using components.
  • #1
Bipolarity
776
2

Homework Statement


Show that [itex] (u \times (v+w))\cdot r = (u \cdot w)(v \cdot r) - (u \cdot v)(w \cdot r) [/itex]

Homework Equations





The Attempt at a Solution


So far I have been able to simplify the LHS to:
[itex] (r \times u)\cdot v + (r \times u) \cdot w [/itex] but don't know how to proceed from there.

In fact, I don't know if this problem is even solvable using only vector identities, i.e. without having to prove using components.

All help is appreciated!

BiP
 
Physics news on Phys.org
  • #2
Hi Bipolarity! :smile:

It's a misprint :rolleyes:

try [itex] (u \times (v \times w))\cdot r = (u \cdot w)(v \cdot r) - (u \cdot v)(w \cdot r) [/itex] :wink:
 
  • #3
Thanks tiny-tim!

BiP
 

1. What is a vector proof?

A vector proof is a mathematical technique used to prove theorems or statements involving vectors. It uses the properties and operations of vectors to show that a statement is true.

2. How do you construct a vector proof?

To construct a vector proof, you must first identify the given information and what you need to prove. Then, use the properties of vectors, such as commutativity, associativity, and distributivity, to manipulate the given vectors and equations to arrive at the desired result.

3. What are some common properties used in vector proofs?

Some common properties used in vector proofs include the commutative property, which states that the order of vector addition does not change the result; the associative property, which states that the grouping of vectors in an addition does not affect the result; and the distributive property, which states that multiplying a vector by a scalar distributes the scalar across the vector.

4. Can vector proofs be used to prove non-vector statements?

Yes, vector proofs can be used to prove non-vector statements as long as the statement can be expressed in terms of vectors. This is because the properties and operations of vectors can be applied to any mathematical statement involving vectors.

5. Are there any tips for successfully solving a vector proof?

Some tips for solving a vector proof include starting with what you know, breaking the proof into smaller steps, and using diagrams or visual representations to aid in understanding. It is also helpful to practice and become familiar with the properties and operations of vectors.

Similar threads

  • Calculus and Beyond Homework Help
Replies
14
Views
596
Replies
10
Views
688
Replies
2
Views
728
  • Calculus and Beyond Homework Help
Replies
1
Views
610
  • Introductory Physics Homework Help
Replies
12
Views
1K
  • Calculus and Beyond Homework Help
Replies
9
Views
770
  • Differential Geometry
Replies
3
Views
1K
  • Precalculus Mathematics Homework Help
Replies
5
Views
3K
  • Calculus and Beyond Homework Help
Replies
1
Views
460
  • Calculus and Beyond Homework Help
Replies
3
Views
693
Back
Top