Posted by **LEON** on Sunday, October 24, 2010 at 10:11pm.

How to prove or disprove

(a)if A has a zeronentryonthe diagonal then A is not invertible

(b)if Ais not invertible then for every matrix B, AB is not invertible

(c)if A is a nonzero 2X2 matrix such that A^2+A=0, then A is invertible

## Answer This Question

## Related Questions

- linear algebra - 1)If A is an invertible matrix and k is a positive integer, ...
- College Math : Linear Algebra - Suppose A is a square matrix satisfying the ...
- Algebra - Let A and B be n x n matrices, assume AB is invertible and show that ...
- math - If A^TA is an invertible matrix, prove that the column vectors of A are ...
- Math - Let A, B, and 0 be 2x2 matrices. Assuming that A is invertible, find a ...
- math - I need help with this one... Thanks!!!! Prove the following statement: ...
- MATHS----Matrix - For a given square matrix A the predicted values of matrix B ...
- Math - Determine whether or not the given linear transformation is invertible. ...
- Matrix - Let A be an invertible n x n matrix, and let B be an n x p matrix. ...
- Algebra - Some functions that aren't invertible can be made invertible by ...

More Related Questions