2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/93122We give a simple, closed-form formula, what we call the Deflation Identity, for converting any 2-qubit circuit with exactly two controlled-U's (and some 1-qubit rotations) into an equivalent circuit with just two CNOTs (and some 1-qubit rotations). We also give two interesting applications of the Deflation Identity; one to "opening and closing a breach" in a quantum circuit, the other to the CS decomposition of a 2-qubit operator.13 pages (8 files: 1 .tex, 2 .sty, 4 .m, 1 .xxx)Quantum Physicstext