Question

Given:

A = V3
B = 2V3
C= 25
D= V16
Which expressions result in a rational number? Select all that apply.

Answer 1

The ones that give a rational number answer are:

C+D

A*B

C*D

A*A

Explanation:

A+B does not give a rational number answer; √3+2√3 = 3√3

C+D is a rational number; √25=5 and √16=4; 5+4=9.

A+D is not a rational number; √3+√16 = √3+4

A*B is a rational number; √3*2√3 = 2√9 = 2*3 = 6

B*D is not a rational number; 2√3*√16 = 2√3*4 = 8√3

C*D is a rational number; √25*√16 = 5*4 = 20

A*A is a rational number; √3*√3 = √9 = 3