### Author Topic: Question on past quiz problem  (Read 862 times)

#### Luhan Zhuang

• Newbie
• Posts: 2
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##### Question on past quiz problem
« on: September 30, 2020, 10:11:56 AM »
Can someone plz help me to solve this problem which is to find the limit as z approaches infinity with steps?

#### RunboZhang

• Sr. Member
• Posts: 51
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##### Re: Question on past quiz problem
« Reply #1 on: September 30, 2020, 09:52:48 PM »
Basically you can substitute z by re^i*theta and use the formula Log(z)=ln|z|+iArg(z)=lnr+i*theta where theta belongs to [-pi, pi). After rearranging you will have a sampled equation and it would be much easier to solve. The pic attached below is my solution, correct me if I am wrong.