What Is the Mathematical Relationship Governing Price in a Simple X Y=k AMM?
In the constant product formula $x cdot y = k$, $x$ and $y$ are the reserves of the two tokens, and $k$ is the constant product. The marginal price of token $Y$ in terms of token $X$ is the ratio of the reserves, $P_{Y/X} = x/y$.
When a trade occurs, the change in reserves $Delta x$ and $Delta y$ must satisfy the equation, and the effective trade price is $Delta x / Delta y$.
