Similar to バナッハの不動点定理

Rank–nullity theorem

Gauss's lemma (number theory)

Angle bisector theorem

Geometric mean theorem

Leibniz formula for determinants

Coupon collector's problem

Casey's theorem

Kőnig's lemma

Primitive Pythagorean triple

Mean value theorem (divided differences)

Shannon's source coding theorem

Noisy-channel coding theorem

Jordan's lemma

Law of sines

Law of tangents

Analyticity of holomorphic functions

Linear independence

Diagonal lemma

Monotone convergence theorem

Intermediate value theorem

Parallelogram law

Taylor's theorem

Dirichlet integral

Thébault's theorem

De Moivre's formula

Ptolemy's theorem

Sz.-Nagy's dilation theorem

Seven circles theorem