\blacksquare - LaTeX Symbol

■

\blacksquare

A filled square symbol often used to denote the end of a proof or to highlight a specific point in mathematical documents.

Examples

P (x) ⟹ Q (x) ■

Denotes the end of a proof in a logical argument.

P(x) \implies Q(x) \blacksquare

The solution is unique ■

Used to emphasize the conclusion of a statement.

\text{The solution is unique} \blacksquare

{x \in R ∣ x^{2} = 1} = {- 1, 1} ■

Marks the end of a set definition or mathematical statement.

\{ x \in \mathbb{R} \mid x^2 = 1 \} = \{-1, 1\} \blacksquare