Theorem imaex

Description: The image of a set is a set. Theorem 3.17 of Monk1 p. 39. (Contributed by JJ, 24-Sep-2021)

	Ref	Expression
Hypothesis	imaex.1	$$⊢A\in \mathrm{V}$$
Assertion	imaex	$$⊢A\left[B\right]\in \mathrm{V}$$

Proof

Step	Hyp	Ref	Expression
1		imaex.1	$$⊢A\in \mathrm{V}$$
2		imaexg	$$⊢A\in \mathrm{V}\to A\left[B\right]\in \mathrm{V}$$
3	1 2	ax-mp	$$⊢A\left[B\right]\in \mathrm{V}$$