Peter K. answered 01/21/20
Math / Statistics / Data Analytics
A rational number is a number is a number that can be written in the form a/b where a and b are integers and b is non-zero. So, since pi - pi = 0, and 0, can be written as 0/ 1, for example, pi - pi must be rational (even though pi is irrational.)
Answers C and D both have √2, an irrational number, as factors when simplified.