1. Evaluate ∫(adsbygoogle = window.adsbygoogle || []).push({}); _{C}(z)/z^{2}+9 dz , where C is the circle │z-2i│=4.

what i have done so far is :

z(t) = 2i + 4e^{it}

z'(t) = 4ie^{it}

f(z(t)) = 4ie^{it}/(4ie^{it})^{2}+9

∫ (4ie^{it}/(4ie^{it})^{2}+9) (4ie^{it}) dt

intergrate from 0->2pi

but i dont know how to solve this intergral, can anyone help?

2. ∫_{c}cos(z)/(z-1)^3(z-5)^2 dz , where C is the circle │z-4│=2.

this z'(t) = 0

so , is this intergral equal 0?

since f(z(t))(z'(t)) = 0

Thanks

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# 2 complex intergrations

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