In mathematics, a theorem is a statement that has been proven on the basis of previously established statements, such as other theorems, and previously accepted statements, such as axioms.
A theorem is a mathematical statement that has been proven from axioms and previously established theorems. Theorems are important results in mathematics which need to be proven and have widespread applications in all fields of mathematics and science, including computer science.
A statement that is believed to be true, but hasn't been proven is called a conjecture or hypothesis. An intermediate result that helps in proving a statement is called a lemma, and like theorems, they also have to be proved.
One of the most famous theorems is the Pythagorean theorem.
- Given a right triangle with known side lengths
a
,b
, meeting at a right angle, the square of the length of the hypotenusec
, opposite to the right angle, is equal to the square of the side lengtha
andb
. Mathematically, that can be stated asc^2 = a^2 + b^2
, orc = sqrt(a^2 + b^2)
- There has been over 300 different proofs, including the similar triangles proof and the proof given by Euclid.
- It is commonplace in geometry and trigonometry. The Pythagorean trigonometric identity states that
sin^2(x) + cos^2(x) == 1
for allx
, and is a corollary of the Pythagorean theorem.
Another famous theorem is the Euclid's theorem.
- There are infinitely many prime numbers.
- The proof has been provided by Euclid's Elements in antiquity.
Theorem Proving automation
It is known that some theorems have been proven using computer assistance, including the famous four color theorem (where no geographical map requires five or more colors if the territories are all contiguous) and the Kepler conjecture, where the best sphere packing is the tie between face-centered cubic and the hexagonal close packing, at 74% filled space.
The field of automated theorem proving, aka ATP has been developed. These include E theorem prover, Isabelle, and ACL2.
Read More
- theorem-proving, an active field in computer science which assists in proving theorems.
- acl2, isabelle: interactive theorem provers
- Wikipedia
- Wolfram Mathworld
- Information about automated theorem proving