Vector Cross Product Homework: Find a×(a-2b+c)

In summary, to find a×(a-2b+c), distribute the cross-product and use the given equations for a×b and c×a. No need to find the components of a, b, and c.
  • #1
Cpt Qwark
45
1

Homework Statement


Given a×b=-i-j+3k and c×a=2i-3j+k, find a×(a-2b+c)

Homework Equations


Cross product (DONE WITHOUT MATRICES).

The Attempt at a Solution


a[/B]×b=c=-(b×a)is all I'm getting to at this point
 
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  • #2
Cpt Qwark said:

Homework Statement


Given a×b=-i-j+3k and c×a=2i-3j+k, find a×(a-2b+c)

Homework Equations


Cross product (DONE WITHOUT MATRICES).

The Attempt at a Solution


a[/B]×b=c=-(b×a)is all I'm getting to at this point
Simply distribute the cross-product.

##\vec{P}\times(\vec{Q}+\vec{R})=\vec{P}\times\vec{Q}+\vec{P}\times\vec{R}##
 
  • #3
Thanks,
so would I have to find the components of a, b, and c?
 
  • #4
Cpt Qwark said:
Thanks,
so would I have to find the components of a, b, and c?
No. Not at all.

What is a×a ?
 
  • #5
Cpt Qwark said:
Thanks,
so would I have to find the components of a, b, and c?

No, you only need the components of axb and axc. Follow SammyS's suggestion.
 
  • #6
Ok thanks guys I got it
 

FAQ: Vector Cross Product Homework: Find a×(a-2b+c)

What is a vector cross product?

A vector cross product is a mathematical operation that takes two vectors as inputs and outputs a third vector that is perpendicular to both of the input vectors. It is commonly used in physics and engineering to calculate forces and torque.

How do I find the cross product of two vectors?

To find the cross product of two vectors, you first need to make sure that the two vectors are in the same dimension. Then, you can use the cross product formula, which is a×b = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1). Plug in the values for each component of the vectors, and the resulting vector will be the cross product.

What does the "a-2b+c" represent in the vector cross product formula?

The "a-2b+c" represents the second vector that is being used in the cross product calculation. The "a" and "c" are the components of the first vector, while the "2b" means that the second vector is being multiplied by a scalar value of 2.

Why is the resulting vector perpendicular to the input vectors?

The resulting vector is perpendicular to the input vectors because of the mathematical properties of the cross product. The cross product of two vectors is always perpendicular to both of the input vectors, creating a 90-degree angle between them.

What are some real-life applications of vector cross product?

The vector cross product has many real-life applications, such as calculating torque in physics, determining the direction of magnetic fields, and designing 3D graphics in computer science. It is also used in engineering for calculating forces and moments in structures and machinery.

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