Which value can a qubit represent in a quantum computing system?

A qubit, or quantum bit, is the fundamental unit of quantum information. Unlike a classical bit, which can only represent a value of either 0 or 1, a qubit has the unique ability to exist in a superposition of states. This means that a qubit can represent not just 0 or 1, but also a combination of both at the same time, as described by quantum mechanics.

Specifically, in a quantum computing system, when a qubit is in the state 0, we denote that as |0⟩, and when it is in the state 1, we denote that as |1⟩. However, it can also represent any linear combination of these states, expressed as a mathematical combination of |0⟩ and |1⟩.

Therefore, the correct representation of a qubit includes both the states of 0 and 1, which is why the answer indicates that a qubit can represent both values simultaneously in its operation within quantum computing. This ability to represent both 0 and 1 at the same time is crucial for the power and advantages of quantum computing over classical computing.