Symbols:Q

The Set of Rational Numbers
$$\Q$$

The set of rational numbers.

Its LaTeX code is \mathbb{Q} or \Q.

The Set of Non-Zero Rational Numbers
$$\Q^*$$

The set of non-zero rational numbers:
 * $$\Q^* = \Q - \left\{{0}\right\}$$.

Its LaTeX code is \mathbb{Q}^* or \Q^*.

The Set of Non-Negative Rational Numbers
$$\Q_+$$

The set of non-negative rational numbers:
 * $$\Q_+ = \left\{{x \in \Q: x \ge 0}\right\}$$.

Its LaTeX code is \mathbb{Q}_+ or \Q_+.

The Set of Strictly Positive Rational Numbers
$$\Q_+^*$$

The set of strictly positive rational numbers:
 * $$\Q_+^* = \left\{{x \in \Q: x > 0}\right\}$$.

Its LaTeX code is \mathbb{Q}_+^* or \Q_+^*.