Bad Qubits — Learn Quantum by Doing

Multiple choice

By Postulate 5, the state space of a composite system is the tensor product of the component spaces. If system A has dimension d_A and system B has dimension d_B, what is the dimension of the joint space?

max(d_A, d_B)
d_A + d_B (dimensions add)
d_A^2 + d_B^2
d_A times d_B (dimensions multiply)