The Complex Derivative at a Point and Analyticity

stihl29
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Homework Statement


f(z) = xy + i(xy+x)

has a derivative at exactly one point after locating the point find the derivative there and give the numerical value is the function analytic at this point?


Homework Equations



My C-R equations are du/dx = y, dv/dy = x, dv/dx = y+1, du/dy = x

The Attempt at a Solution


i don't really know how to interpret the C-R equations.
answer is z = -1/2 - i/2 f ' = -1/2 + i/2 and not analytic
 
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CR actually means a relation satisfied by the partial derviatives for a complex function to be analytic (holomorphic)

you have only given the partial derivatives, do you know the CR equations?
 
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