Metamath Proof Explorer


Theorem 9ne0

Description: The number 9 is nonzero. (Contributed by SN, 22-Oct-2025)

Ref Expression
Assertion 9ne0 9 ≠ 0

Proof

Step Hyp Ref Expression
1 9nn 9 ∈ ℕ
2 1 nnne0i 9 ≠ 0