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Math Challenge II-A Spring Number Theory Homework 5.21

 
 
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Math Challenge II-A Spring Number Theory Homework 5.21
by James Zhang - Thursday, 30 March 2023, 5:57 PM
 

Can I have a clarification of what we are supposed to do in this question? Also, can I get an example on how to do the question?

 
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Re: Math Challenge II-A Spring Number Theory Homework 5.21
by John Lensmire - Friday, 31 March 2023, 10:19 AM
 

Think of this question as exploring the ideas we looked at in 5.1. For part (a) of 5.21, we want to make tables of the multiples of 5 and 6 (mod 8) like we did in class for multiples of 3 (mod 11):


For part (b), we want to find mod. mult. inverses for numbers (mod) 8 (where they exist). Recall they only exist for numbers relatively prime to 8. For example, 1 is it's own inverse, as is 7. What about the other number relatively prime to 8?

Hope this helps! Let us know if you have any follow-up questions.