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Metamath Proof Explorer

Theorem sqnegd

Description: The square of the negative of a number. (Contributed by Igor Ieskov, 21-Jan-2024)

		Ref	Expression
	Hypothesis	sqnegd.1	$⊢ φ \to A \in ℂ$
	Assertion	sqnegd	$⊢ φ \to {(- A)}^{2} = A^{2}$

Step	Hyp	Ref	Expression
1		sqnegd.1	$⊢ φ \to A \in ℂ$
2		sqneg	$⊢ A \in ℂ \to {(- A)}^{2} = A^{2}$
3	1 2	syl	$⊢ φ \to {(- A)}^{2} = A^{2}$