Cauchy-Riemann equations

[ koh-shee-ree-mahn, koh-shee- ]
/ ˈkoʊ ʃiˈri mɑn, koʊˈʃi- /

plural noun Mathematics.

equations relating the partial derivatives of the real and imaginary parts of an analytic function of a complex variable, as f(z) = u(x,y) + iv(x,y), by δux = δvy and δuy = −δvx.

Origin of Cauchy-Riemann equations

named after A. L. Cauchy and G. F. B. Riemann