Ok then an example that would disprove this as a subspace would be
[[3,13][3,13]]+[[5,5][7,7]] = [[8,18][10,20]]
det of [[8,18][10,20]] = -20 so it fails
Homework Statement
Determine whether all 2x2 matrices with det(A) = 0 are a subspace of M2x2, the set of all 2x2 matrices with the standard operations of addition and scalar multiplication.Homework Equations
Must pass in order to be a subspace
Closure property of addition - If w and v are...
Well my main question is, would B2x2 pass the closure property of addition because when you add another thing to it that's not symmetric it, it looses its symmetry. Would that matter.
So does it pass that axiom or not is what I'm asking.
Homework Statement
The set of all matrices A2x2 forms a vector space under the normal operations of matrix + and Scalar multiplication. Does the set B2x2 of all symmetric matrices form a subspace of M2x2? Explain.
Homework Equations
AT = A
Closure property of addition - If w and v are...
I'm trying to figure out how to set up a matrix where I don't know the last value ex a+2+4=x, b+4+6=x, c+2+6=x.
Would it be something like this?
[1,0,0,x-6]
[0,1,0,x-10]
[0,0,1,x-8]
so factoring out the 12 will get me a 12[x^3-X^2-5X+2]=0 and the root theorem says my it should be +-(2,1)/1 Right? So possible answers are +2, -2, or 1 and -1