When does the square root of "n" represent a rational number?
a. n is a perfect square
b. n is a positive integer
c. n can be written as a ratio
d. n can be any real number
Which is it and please explain.
n is a perfect square means that there is a rational number k such that k*k = n
Then k is the square root.
The others are clearly false, since
√5 is not rational
√(3/5) is not rational
Therefore, certainly not (d)