Metamath Proof Explorer


Theorem dgr1term

Description: The degree of a monomial. (Contributed by Mario Carneiro, 26-Jul-2014)

Ref Expression
Hypothesis coe1term.1 ⊢ F = z ∈ ℂ ⟼ A ⁢ z N
Assertion dgr1term ⊢ A ∈ ℂ ∧ A ≠ 0 ∧ N ∈ ℕ 0 → deg ⁡ F = N

Proof

Step Hyp Ref Expression
1 coe1term.1 ⊢ F = z ∈ ℂ ⟼ A ⁢ z N
2 1 coe1termlem ⊢ A ∈ ℂ ∧ N ∈ ℕ 0 → coeff ⁡ F = n ∈ ℕ 0 ⟼ if n = N A 0 ∧ A ≠ 0 → deg ⁡ F = N
3 2 simprd ⊢ A ∈ ℂ ∧ N ∈ ℕ 0 → A ≠ 0 → deg ⁡ F = N
4 3 3impia ⊢ A ∈ ℂ ∧ N ∈ ℕ 0 ∧ A ≠ 0 → deg ⁡ F = N
5 4 3com23 ⊢ A ∈ ℂ ∧ A ≠ 0 ∧ N ∈ ℕ 0 → deg ⁡ F = N