Are the following expressions polynomials? Justify your answer:
$\frac{1}{x+1}$

(N/A) polynomial is an algebraic expression in which the exponents of the variable are non-negative integers (whole numbers).
The given expression is $\frac{1}{x+1} = (x+1)^{-1}$.
In this expression,the exponent of the variable $x$ is $-1$,which is not a whole number.
Therefore,the given algebraic expression is not a polynomial.