Complex Variables Homework: Determine Set, Compute Derivative

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Homework Statement



Determine the set on which f(z) = 1/(z^3 +1) is analytic and compute its derivative.

Homework Equations



Hint: you do not need to appeal to the Cauchy-Riemann equations

The Attempt at a Solution


Total stuck with this one. everything we have done this far has been using the c-r equations.

Thanks for any input.
 
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Ask yourself:

1) Are there any values of z for which f(z) is not defined? If so, what are they, and what does it tell you about the analyticity of the function?

2) When can you treat taking a derivative of a complex function ##\frac{df(z)}{dz}## just like taking a derivative of a real function?
 
Are the function and derivatives defined everywhere?
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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