If the arc sandwiched between two chord angles is equal, then the two chord angles are also equal; Theorem of Intersecting Chords The length of two intersecting chords in a circle divided by the product of the intersection point is equal; If the chord intersects the diameter vertically, then half of the chord is the proportional average of two line segments formed by its separate diameters.

Math:

Mathematics is a subject that studies concepts such as quantity, structure, change, space and information. Mathematics is a universal means for human beings to strictly describe the abstract structure and mode of things, and can be applied to any problem in the real world. All mathematical objects are artificially defined in essence. In this sense, mathematics belongs to formal science, not natural science. Different mathematicians and philosophers have a series of views on the exact scope and definition of mathematics.