To check –1 is a Rational Number or not.
Firstly we discuss rational numbers
We know that a rational number is a number that can be written in the form of \frac{p}{q} where p, q \in Z and q ≠ 0. The numbers 25, 3.765, 4.5, etc., are rational numbers. can be reduced to the form \frac{p}{q} where p, q Z, and q ≠ 0 because \sqrt{25}=5
Examples of rational numbers:
i) 0.26= is a rational number.
ii) 3.6666… is a recurring decimal, it is a rational number.
iii) 5.333…is a rational number.
iv) 0.142857142857… is a rational number.

since we may write -1 in the form of \frac{-p}q . i.e, \frac{-1}1=-1
Hence clearly -1 is a rational number.
is -3 a rational number:
since we may write -3 in the form of \frac{-p}q . i.e, \frac{-3}1=-3
Hence clearly -3 is a rational number.