Area of a parallelogram with vectors

In summary, the formula for finding the area of a parallelogram using vectors is A = ||a x b||, where a and b are the two adjacent sides of the parallelogram and ||a x b|| represents the magnitude of the cross product of the two vectors. The area of a parallelogram can be negative if the two vectors used to calculate it are pointing in opposite directions. To find the area of a parallelogram in three-dimensional space, the same formula can be used, but the magnitude of the resulting vector must be found. Not any two sides of a parallelogram can be used to calculate its area with vectors, as they must be adjacent and not parallel. The area of a parallelogram with
  • #1
ganondorf29
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0

Homework Statement


Determine the area of the parallelogram spanned by the vectors
< 0, 9, 6 > and < −10, −6, −4 >


Homework Equations


Area = A X B

The cross product of < 0, 9, 6 > and < −10, −6, −4 > = 0i - 60j + 90k

The Attempt at a Solution



I know the area is the cross product of A X B, but the examples that I have done did not have a k value. ex <3,-3,0> X <2,3,0> What do I do now that I have a k value?
 
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  • #2
Area is a real number. Not a vector. It's |AxB|. You need to find the length of the cross product vector.
 
  • #3
Thank you, I got it.
 

Question 1: What is the formula for finding the area of a parallelogram using vectors?

The formula for finding the area of a parallelogram using vectors is A = ||a x b||, where a and b are the two adjacent sides of the parallelogram and ||a x b|| represents the magnitude of the cross product of the two vectors.

Question 2: Can the area of a parallelogram be negative?

Yes, the area of a parallelogram can be negative if the two vectors used to calculate it are pointing in opposite directions. This indicates that the parallelogram is oriented in the opposite direction of the normal convention.

Question 3: How do you find the area of a parallelogram with vectors in three-dimensional space?

To find the area of a parallelogram in three-dimensional space, you can use the same formula as in two-dimensional space, A = ||a x b||. However, in three-dimensional space, the cross product of two vectors results in a vector perpendicular to both of the original vectors. Therefore, you would need to find the magnitude of this resulting vector to get the area.

Question 4: Can you use any two sides of a parallelogram to calculate its area with vectors?

No, you cannot use any two sides of a parallelogram to calculate its area with vectors. The two sides must be adjacent and not parallel to each other in order to use the cross product formula.

Question 5: How is the area of a parallelogram with vectors related to the determinant of the matrix formed by the two vectors?

The area of a parallelogram with vectors is equal to the absolute value of the determinant of the matrix formed by the two vectors. This is because the determinant represents the signed area of the parallelogram, and taking the absolute value removes any negative sign.

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