Multiple choice
Run this circuit, then measure all 2 qubits at once. What is the probability of the joint outcome |10⟩ (qubit 0 leftmost)?
// |00> --x(1)--> |01> --h(0)--> (|01>+|11>)/sqrt2 --cx(0,1)--> (|01>+|10>)/sqrt2 // --z(0)--> (|01>-|10>)/sqrt2, the singlet. const c = circuit(2); c.x(1); c.h(0); c.cx(0, 1); c.z(0); return c;
Commit your prediction for P(|10⟩) — then run it.