Question

1. which is a polynomial?

$3x^{\frac{1}{2}}$
$3x^{\frac{1}{3}} + 5x$
$x^2 + 5x + 10$
$\sqrt{x}$

Explanation:

A polynomial is a sum of terms where each term has a variable raised to a non-negative integer exponent. $3x^{1/2}$ has a fractional exponent, $3x^{1/3}+5x$ has a fractional exponent, $\sqrt{x}=x^{1/2}$ has a fractional exponent—all invalid. $x^2 +5x +10$ has terms with exponents 2, 1, 0 (non-negative integers), so it is a polynomial.

Answer:

$x^2 + 5x + 10$