Victor Camocho
math2250fall2011-2
WeBWorK assignment number Homework 6 is due : 09/29/2011 at 11:00pm MDT.
The
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(b)
if your answer
is yes,
.
1. (1 pt) Library/Rochester/setAlgebra34Matrices/inverse3x3b.pg


1
2
3
-3
-2  ,
Given the matrix  3
19 -25 -20
(a) does the inverse of the matrix exist?
Your answer is (input Yes or No):
(b)
the inverse here:

 if your answer is Yes, write

write the inverse here:
4. (1pt) Library/Rochester/setAlgebra34Matrices/matrixmult3.pg



-4 -4 0
1 -1 2
If A = 3 3 -3  and B = -2 -2 1 
3 1 0
2 1 3


Then AB =
.
2. (1 pt) Library/Rochester/setAlgebra34Matrices/sw7
6 3.pg
3 0
Given the matrix
,
5 5
(a) find its determinant;
Your answer is :
(b) does the matrix have an inverse?
Your answer is (input Yes or No) :



and BA =

5.
(1 pt) Library/Rochester/setLinearAlgebra4InverseMatrix-
/ur la 4 8.pg
Determine which of the formulas hold for all invertible n × n
matrices A and B
•
•
•
•
•
•
3. (1 pt) Library/Rochester/setAlgebra34Matrices/inverse2x2.pg
8 2
Given the matrix
,
2 -4
(a) does the inverse of the matrix exist?
Your answer is (input Yes or No) :
c
Generated by the WeBWorK system WeBWorK
Team, Department of Mathematics, University of Rochester
1
A. (A + B)2 = A2 + B2 + 2AB
B. (In − A)(In + A) = In − A2
C. A5 is invertible
D. A + In is invertible
E. (AB)−1 = A−1 B−1
F. AB = BA