Let X, Y and f be given.

Assume H1.

Let y be given.

Assume Hy: y ∈ Y.

Apply H1 y Hy to the current goal.

Let x be given.

Assume H2.

An exact proof term for the current goal is Eps_i_ax (λx ⇒ x ∈ X ∧ f x = y) x H2.

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