Ohh ok do you mean that if Ax is in the null space then:
Nul(A) must contain the zero vector
If x ∈ Nul(A) and y ∈ Nul(A), then x + y ∈ Nul(A) (aka closed under addition)
If x ∈ Nul(A) and c is a scalar, then cx ∈ Nul(A) (aka closed under scalar multiplication)
Just say that P^3 is isomorphic to R^4 and then convert those vectors into a corresponding matrix and row reduce and your pivotal columns will tell you what vectors are linearly independent.
Ok so the column space of A consists of all possible products Ax for any x an element of R^n. So if the Col(A) is equal to the Nul(A) which is the set of all vectors x for which Ax = 0 then this tells us that Ax must be equal to zero? aka the linear combination must be equal to 0?
I'm really confused what do you mean by A^2? Are you saying that A is the identity matrix? I guess I'm just confused in general about WHEN the column is EVEN equal to the null space at all.. How can you tell?
Homework Statement
Find all 10x10 Matrices such that the column space is equal to the null space.
Homework Equations
Choose Function: n!/k!(n-k)!
where n is the total number of elements and k is the number k-cominations of the set.
rankA+dimNulA=n for a matrix in R^n
The...