Calculating Vectors: A, B, and C

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Homework Statement


I cannot find other sources to help me with this problem set, I have A B and C vectors defined by: A (2,1,1) B(1,-1,0), C(-1,1,-1)
From these I have a list of questions and some I am stuck on are:each of these are vectors with an arrow above it
1. |A| + |B| this I did as √ax^2 +ay^2 +az^2 + √the same for B
2. |A + B| but how do i do this, what is the difference between these?

3. A + B

4. 3C

5. A dot (B X C)

8. What is the angle between A and B, A and C, and B and C? in radians use pi

id appreciate any help!
 
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organgeatom said:
1. |A| + |B| this I did as √ax^2 +ay^2 +az^2 + √the same for B

This would be correct.

organgeatom said:
2. |A + B| but how do i do this, what is the difference between these?

This is asking for you the magnitude of (vector A + vector B), question 1 was asking you for the magnitude of vector A + the magnitude of vector B. Start by first calculating what A+B is, how do you add two vectors together?


organgeatom said:
3. A + B

The same as question 2.


organgeatom said:
4. 3C

Do you know how to multiply a vector by a scalar?

organgeatom said:
5. A dot (B X C)

Do you know the terms 'dot product' and 'cross-product'?

organgeatom said:
8. What is the angle between A and B, A and C, and B and C? in radians use pi

This question depends on if you can do question 5.