Solving for Vectors a, b, and c - Help Appreciated

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To solve for nonzero vectors a, b, and c such that a x b = a x c with b not equal to c, the key is to ensure that c is a linear combination of b and a. The discussion highlights that the cross product is zero for parallel vectors, allowing for solutions like (1,1,1) x (2,2,2) = (1,1,1) x (3,3,3) = (0,0,0). A valid approach is to express c as c = b + ka, where k is a nonzero scalar, ensuring that c is distinct from b while maintaining the required cross product equality. The conversation emphasizes correcting misconceptions about the properties of cross and dot products in vector mathematics. Understanding these relationships is crucial for solving the problem effectively.
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Hello, can anyone guide me with this problem?

Find nonzero vectors a ,b , and c such that a x b = a x c but b does not equal c

I would appreciate any help. Thanks
 
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The cross product is zero for perpendicular vectors so the cartesian unit vectors would satisfy that as i x j = i x k =0.
 
inha said:
The cross product is zero for perpendicular vectors so the cartesian unit vectors would satisfy that as i x j = i x k =0.

That's all wrong. The dot product is zero for perpendicular vectors.
The cross product is i x j = k.
 
Antiphon said:
That's all wrong. The dot product is zero for perpendicular vectors.
The cross product is i x j = k.
Yeah, the cross product is zero for parallel vectors. So (1,1,1) x (2,2,2)= (1,1,1) x (3,3,3) = (0,0,0) is a solution.
 
Oh hell. I got my products mixed. Scratch that advice and sorry if I caused any problems.
 
We just need that c=b+ka so that c-b is parallel to a
(a,b,b+ka) satisfies the prop(k is a scalar not equal to zero)
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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