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Old November 1st, 2007, 10:17 PM
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Quote:
Originally Posted by Liav Teichner View Post
I need to decide whether the following statement is true or not:
let f be a complex function, f(z)=f(x+iy)=u(x,y)+iv(x,y).if u and v satisfy the Cauchy-Riemann equations in a neighborhood of z_0 then f is differentiable at z_0.
no. consider f(z) = u(x,y) + iv(x,y), where u(x,y) = \sqrt{|xy|}, v(x,y) = 0 and consider the derivative at z_0 = 0

i got this example from a text book.

can you come up with a nicer example, TPH?
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