Similar to 5項補題

Proof that 22/7 exceeds π

Proof that π is irrational

Euler's formula

Interesting number paradox

Open mapping theorem (complex analysis)

Rank–nullity theorem

Angle bisector theorem

Carathéodory's theorem (convex hull)

Geometric mean theorem

Leibniz formula for determinants

Locally connected space

Coupon collector's problem

Casey's theorem

Primitive Pythagorean triple

Kempner series

Cauchy's mean value theorem

Mean value theorem (divided differences)

Schiffler point

Shannon's source coding theorem

Noisy-channel coding theorem

Jordan's lemma

Sylvester–Gallai theorem

Stewart's theorem

Law of sines

Law of tangents

Analyticity of holomorphic functions

Linear independence