Theorem lem1d

Description: A number minus 1 is less than or equal to itself. (Contributed by Mario Carneiro, 28-May-2016)

	Ref	Expression
Hypothesis	ltp1d.1	$$⊢\phi \to A\in ℝ$$
Assertion	lem1d	$$⊢\phi \to A-1\le A$$

Proof

Step	Hyp	Ref	Expression
1		ltp1d.1	$$⊢\phi \to A\in ℝ$$
2		lem1	$$⊢A\in ℝ\to A-1\le A$$
3	1 2	syl	$$⊢\phi \to A-1\le A$$