Question

Which of the following is not a polynomial?

• A. $5x^2+2x+11$
• B. $x^3+4$
• C. $\sqrt{x}+1$
• D. $x^2-9$

Answer 1

The correct option is C $\sqrt{x}+1$

For an algebraic expression to be a polynomial, the power of the variables must always be a whole number.

The expression,
$\sqrt{x}+1$

can also be written as
$x^{0.5}+1$

In the above expression , the power of the variable $x$ is 0.5, which is not a whole number.
Hence, it is not a polynomial.