SOLUTION: Critical thinking Suppose A is a whole number and B is an irrational number. Is it possible for the product of AB to be a rational number? Explain why or why not?

Algebra.Com
Question 124041: Critical thinking
Suppose A is a whole number and B is an irrational number. Is it possible for the product of AB to be a rational number? Explain why or why not?

Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!
We are given A is a whole number and B is irrational. Let's assume that the product A*B is rational. That means that there are two integers p and q such that .

Dividing both sides of the equation by A results in:

.

p was chosen as an integer, and since A is a whole number and q is an integer, Aq must be an integer. Therefore is a rational number.

But that means B must be rational, contradicting the given condition that B be irrational. Therefore the assumption that A*B is rational must be false and A*B must be irrational.


RELATED QUESTIONS

Suppose a is a whole number and b is an irrational number. Is it possible for the... (answered by stanbon)
Suppose a is a whole number and b is an irrational number. Is it possible for the broduct (answered by HyperBrain)
Suppose a is a whole number and b us an irrational number. Is it possible for the product (answered by richwmiller)
Explain why the product of a nonzero rational number and an irrational number is... (answered by solver91311)
Why is the product of a non zero rational number and an irrational number irrational... (answered by MathLover1)
5)Which number can be multiplied to a rational number to explain that the product of a... (answered by hkwu)
Jacinta says the product of a rational number and an irrational number is always... (answered by jim_thompson5910)
Show that the product of a non-zero rational number and an irrational number is an... (answered by ikdeep)
What is the reasoning behind the fact that it is not possible for the solution of an... (answered by jim_thompson5910)