Extra Credit 2

Due: October 22, 2025
Points: 40

Short Answer

Answer these questions in one or two sentences.

1. (10 points) Find a news article or blog post that describes something about security that is incorrect. Submit the article or post (a URL or a DOI that enables us to read the article or post is sufficient and explain why it is incorrect.

Longer Answer

Remember to write clearly (if you need help, go to the Writing Center on campus) and justify your answers!

2. (30 points) Prove that, if n = pq, that φ(n) = (p−1)(q−1).

Matt Bishop Office: 2209 Watershed Sciences Phone: +1 (530) 752-8060 Email: mabishop@ucdavis.edu

ECS 235A, Computer and Information Security Version of October 12, 2025 at 10:52PM

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