Professor Kate Poirier, Spring 2017

Author: Kenny

Test 3 #2

2) MNULNYX ZLIG NBY VINNIG HIQ QY BYLY. MNULNYX ZLIG NBY VINNIG HIQ GS QBIFY NYUG BYLY.

a) +6

b) Unencrypted ABCDEFGHIJKLMNOPQRSTUVWXYZ
Encrypted       GHIJKLMNOPQRSTUVWXYZABCDEF

c) STARTED FROM THE BOTTOM NOW WE HERE. STARTED FROM THE BOTTOM NOW MY WHOLE TEAM HERE.

Test 1 solution #4

4a. Prove that if x is a rational number and x ≠ 0 then 1/x is a rational number

If x is a rational number ≠ 0, then it can be written as a/b, where a and b are integers and ≠ 0. Then 1/x is equal to 1/(a/b) which equals b/a. Therefore if x is a rational number, 1/x is also rational.

4b. Prove that if x is an irrational number and x≠ 0 then 1/x is an irrational number.

Assume that x is irrational and 1/x is rational. Then 1/x can be written as a/b where a and b are integers ≠ 0. So x is equal to 1/(a/b) which equals b/a, b and a are integers. Therefore x is rational. This contradicts the assumption that x is irrational. Therefore it is true that if x is irrational, 1/x is also irrational.

Introducing Kenny Pang

My name is Kenny Pang and my major is Applied Math. I got interested in math because I find it quite easy. I always get high grades in math classes without having to study much. I currently don’t have any goals after graduation. Maybe I will find a job and work for a couple of years then I may decide to do something else. What I hope to get out of this course is the programming knowledge which may help me in the future. Some of my hobbies are playing video games and watching movies.