Let x and y be given.

Assume Hx Hy Hy0.

rewrite the current goal using mul_SNo_com y (x :/: y) Hy (SNo_div_SNo x y Hx Hy) (from left to right).

An exact proof term for the current goal is mul_div_SNo_invL x y Hx Hy Hy0.

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