Expression (5x² - 2x + 7), (
) and (y⁵ - √(5y²) + 7) are polynomials.
<h3>What is a polynomial ? </h3>
A polynomial is a type of algebraic expression where exponents of all variables are whole number.
1) 5x² - 2x + 7
Since there are no variables raised to negative or fraction exponents,
the expression is a polynomial.
2) 
Since there are no variables raised to negative or fraction exponents,
the expression is a polynomial.
3) y⁵ - √(5y²) + 7
This can be re-written as

Since there are no variables raised to negative or fraction exponents,
the expression is a polynomial.
4) 
This can be re-written as

Since variable y is raised to a fraction exponent,
the expression is not polynomial.
Therefore, expression (5x² - 2x + 7), (
) and (y⁵ - √(5y²) + 7) are polynomials.
Learn more about polynomials here: brainly.com/question/17822016
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