Evaluate the countour integral $\int _\Gamma z dz$

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Can someone please help me setup

a) $\int _\Gamma z dz$

b) $\int _\Gamma \bar z dz$

and given the admissible parametrization of $\Gamma$

$\Gamma_1 : z_1: 2 + i(t - 1) ; 1 \leq t \leq 2$

and $\Gamma_2 : z_2: (3 - t)(2 + i) ; 2 \leq t \leq 3$

Is it $\int _\Gamma z dz = \int_{1}^{2} 2 + i(t - 1)dt + \int_{2}^{3} (3 - t)(2 + i) dt$ ?

For the part b) I don't know even how to start.

I would really appreciate if you anyone can set up the problem. Thank you

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I think that what could help you is the expression $$\int_\Gamma f(z) dz = \int_a^b f(\Gamma(t))\Gamma'(t)dt.$$

For example, in the first case, your $F(z) = z$, $\Gamma(t) = 2 + i(t-1)$, $a = 1$, $b = 2$ and $\Gamma'(t) = i$. So you get that $$\int_\Gamma f(z) dz = \int_1^2 (2 + i(t-1))idt. = (2it - \frac{t^2}{2} + t)\big|_{t=a}^b = -\frac{1}{2} + 2i$$

For the second part, you will need to calculate $\overline{\Gamma(t)}$, but it shouldn't be too difficult.