What are the values of a that make A=0?

  • Thread starter Thread starter ~Sam~
  • Start date Start date
AI Thread Summary
To determine the values of 'a' that make the determinant of matrix A equal to zero, cofactor expansion is suggested as the method of approach. The matrix A is given as a 3x3 matrix with variable 'a' in multiple positions. Participants express confusion about how to apply cofactor expansion effectively in this scenario. The discussion emphasizes the need for clarity in the calculations involved in finding the determinant. Ultimately, the goal is to identify all values of 'a' that satisfy the condition A=0.
~Sam~
Messages
70
Reaction score
0

Homework Statement



if
A=
a 3 5
a -7 6
5 4 a

find all values of a that make A=0. Give your answer as a comma-separated list.

Homework Equations



Looks like the cofactor expansion would be used

The Attempt at a Solution



I'm really lost in this one.
 
Physics news on Phys.org
~Sam~ said:
Looks like the cofactor expansion would be used
What did you get by using it?
 

Thread 'Family of lines that are at a distance of 5 from the origin'

I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...
View full post »

Similar threads

Can this be solved without trial and error?
Replies
6
Views
1K
Are these values of the following correct? (Complex cube root of unity)
Replies
9
Views
2K
Find integer points on this equation
Replies
8
Views
1K
Verify that ## L(1, \chi)\neq 0 ##
Replies
4
Views
1K
Solve the simultaneous equations involving x, y, and their squares
Replies
2
Views
1K
Compute the number of positive integer divisors of 10
Replies
2
Views
2K
Find the expected value of a coin flipping game
Replies
7
Views
3K
Need help in manipulating rational absolute value inequalities
Replies
11
Views
2K
How do you solve cos(α+θ)=0 for different values of α?
Replies
21
Views
2K
Given f(N) as digital signal, find f(2N -1)
Replies
2
Views
2K

Hot Threads

Recent Insights

Back
Top