Similar to ナジーの伸張定理

Jordan's lemma

Sylvester–Gallai theorem

Stewart's theorem

Law of sines

Law of tangents

Analyticity of holomorphic functions

Linear independence

Diagonal lemma

Thales's theorem

Monotone convergence theorem

Ceva's theorem

Intermediate value theorem

Parallelogram law

Taylor's theorem

Dirichlet integral

Thébault's theorem

De Moivre's formula

Ptolemy's theorem

Seven circles theorem

Napkin ring problem

Lazy caterer's sequence

Newton's theorem (quadrilateral)

Proof that e is irrational

Hardy–Littlewood inequality

Pappus's area theorem

Pappus's hexagon theorem

Banach fixed-point theorem

Tangent half-angle substitution