Let x and y be given.

Assume Hx Hy Hy0.

rewrite the current goal using mul_div_SNo_R x y y Hx Hy Hy (from right to left).

We will prove (x :/: y) * y = x.

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

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