Nonsingularity of matrix of squares (help)

In summary, the question is about proving that the matrix Q2, which is the square of the entries of an orthogonal matrix Q, is nonsingular. The conversation suggests trying to find examples and using results about the Hadamard or Schur product to solve the problem.
  • #1
monguss
1
0
Need help to prove (or disprove, hope not) this result:

Let Q=[q_ij] be a orthogonal matrix (Q^T*Q=Identity) and let Q2 be the matrix of the squares of the entries of Q, that is Q2=[q^2_ij]. I need to prove that Q2 is nonsingular.


Been trying with some results about the Hadamard or Schur porduct in the sense that Q2=Q.Q
where the dot . represents the Schur product!

Any ideas

Thanks

Monguss
 
Physics news on Phys.org
  • #2
monguss said:
Need help to prove (or disprove, hope not) this result:

If you don't know what the answer is supposed to be, it helps to make some examples up. Write down three orthogonal matrices, square their entries and see if the results are all invertible. If not you're done, if yes maybe you'll get some insight into what exactly is making them invertible when examining the inverses
 

1. What is the meaning of nonsingularity in matrices?

Nonsingularity in matrices refers to a property of a square matrix where it has a determinant that is not equal to zero. This means that the matrix is invertible, and its inverse exists.

2. How do you determine if a matrix is nonsingular?

To determine if a matrix is nonsingular, you can calculate its determinant. If the determinant is not equal to zero, then the matrix is nonsingular. Another way is to check if the matrix has a unique solution when solving a system of linear equations. If it does, then the matrix is nonsingular.

3. What is the consequence of a singular matrix?

A singular matrix has a determinant of zero, which means that it is not invertible. This can cause problems in solving systems of linear equations as there will either be no solution or an infinite number of solutions. It can also affect other operations on matrices, such as finding the inverse or calculating eigenvalues.

4. Can a matrix be nonsingular and singular at the same time?

No, a matrix can either be nonsingular or singular, but not both. If a matrix has a determinant of zero, it is singular, and if it has a non-zero determinant, it is nonsingular.

5. How does nonsingularity affect the properties of a matrix?

Nonsingularity affects the properties of a matrix in several ways. Firstly, nonsingular matrices have an inverse, which allows for easier solving of systems of linear equations and other operations. Secondly, nonsingular matrices have unique solutions, which can be important in certain applications. Finally, nonsingular matrices have non-zero determinants, which means they have full rank and are not linearly dependent.

Similar threads

Replies
5
Views
5K
Replies
2
Views
2K
Replies
6
Views
775
  • Linear and Abstract Algebra
Replies
4
Views
9K
  • Linear and Abstract Algebra
Replies
4
Views
7K
  • Linear and Abstract Algebra
Replies
7
Views
3K
Replies
6
Views
1K
  • Linear and Abstract Algebra
Replies
14
Views
3K
  • Calculus and Beyond Homework Help
Replies
1
Views
2K
  • Linear and Abstract Algebra
Replies
2
Views
2K
Back
Top