Integration (related to contour integration)

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Typeset homework problem 8 (15 points): f(z) analytic on disk |z| ≤ R, C the circle |z| = R; part (a) gives Cauchy-type formula f(z) = (1/(2πi)) ∮ f(t)[1/(t−z) − 1/(t−z*)] dt with z* = R²/z̄; part (b) gives Poisson's integral formula for u(r,θ).

As the tutorial has not covered this topic yet, I'm quite confused on this question. (there is another question about this topic too, but I would like to try that question after knowing how to do this question)
Q.8 (a) (I'm not sure whether I will know how to do (b) after having (a) done, I just ask (a) first)
[itex]C: t=Re^{i\theta}\\<br /> dt=iRe^{i\theta}d\theta\\<br /> R.H.S.=\frac{1}{2\pi i}\oint_{C}f(t)[\frac{1}{t-z}-\frac{1}{t-z^*}]dt\\<br /> =\frac{1}{2\pi i}\oint_{C}\frac{f(t)}{t-z}dt-\frac{1}{2\pi i}\oint_{C}\frac{f(t)}{t-z^*}dt\\<br /> =\frac{1}{2\pi i}\int_{0}^{2\pi}\frac{f(Re^{i\theta})}{Re^{i\theta}-z}iRe^{i\theta}d\theta-\frac{1}{2\pi i}\int_{0}^{2\pi}\frac{f(Re^{i\theta})}{Re^{i\theta}-z^*}iRe^{i\theta}d\theta\\<br /> =\frac{R}{2\pi}\int_{0}^{2\pi}\frac{f(Re^{i\theta})}{Re^{i\theta}-z}e^{i\theta}d\theta-\frac{R}{2\pi}\int_{0}^{2\pi}\frac{f(Re^{i\theta})}{Re^{i\theta}-z^*}e^{i\theta}d\theta[/itex]

I'm confused that whether I should do it like this.
When I go to this step, I do not know what should I do to integrate it.
I have tried integration by part but I then got a more complicated one...
Can anyone help me? Thank you.