Assume Heq: Zplus = rational_numbers.

We will prove False.

We prove the intermediate claim H0Q: 0 ∈ rational_numbers.

An exact proof term for the current goal is zero_in_rational_numbers.

We prove the intermediate claim H0Z: 0 ∈ Zplus.

rewrite the current goal using Heq (from left to right).

An exact proof term for the current goal is H0Q.

An exact proof term for the current goal is (zero_not_in_Zplus H0Z).

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