CX Little/Big Endian Misunderstanding

[ohadlev77]

Hello,

As a beginner in quantum computing and Qiskit I have already figured out that Qiskit is using the Little Endian method when dealing with qubits. Thus the matrix of the CX gate in Qiskit is:

[1 0 0 0
0 0 0 1
0 0 1 0
0 1 0 0]

Whilst in other places (who uses the Big Endian method) the matrix of the CX gate is:

[1 0 0 0
0 1 0 0
0 0 0 1
0 0 1 0]

So far so good.
But then I encountered [this](https://learn.qiskit.org/course/introduction/entangled-states#entangled-30-0) problem in the Qiskit introduction course - and it looks like that the CX matrix applied is the second one above.

For that code:

MESSAGE = '11'
qc_alice = QuantumCircuit(2,2)

if MESSAGE[-1]=='1':
qc_alice.x(0)
if MESSAGE[-2]=='1':
qc_alice.x(1)

qc_alice.h(1)
qc_alice.cx(1,0)

ket = Statevector(qc_alice)
ket.draw()

I expected the result: -[1/sqrt(2)]|01> + [1/sqrt(2)]|11>
But the result is: [1/sqrt(2)]|01> - [1/sqrt(2)]|10>

What am I missing?
Thanks a lot!