1. A line segment connecting any two points on a circle is called a chord.

2. Refers to the hypotenuse of a right triangle.

The chord passing through the center of the circle is called the diameter, and the diameter is the longest chord in a circle. The sum of squares of the sides of two right angles (short hook and long strand) is equal to the square of the side length of the hypotenuse (chord).

In geometry, if both endpoints of a line segment are on a curve, the line segment is called the chord of the curve.

Extended data:

Intersecting chord theorem;

The length of two intersecting chords in a circle divided by the product of the intersection point is the same. Draw two chords through a point in a circle, and the product of two line segments divided by the point is equal.

Pythagorean theorem:

Written language: The sum of the squares of the sides of two right angles (short hook and long strand) is equal to the square of the side length of the hypotenuse (chord).

Symbolic language: a? +b？ =c？

The knowledge about strings in senior middle schools includes cosine theorem, sine theorem, cotangent theorem, cosine theorem and so on.