Which algebraic expressions are polynomials? check all that apply. 2x^3 - 1/x x^3y - 3x^2 + 6x y^2 + 5y - √ 3 2-√ 4x -x√ 6 -1/3^x3 - 1/2^x2+ 1/4

1. is not a polynomial, because the degree of second term is negative (-1);

2. is a polynomial of 4th degree (the highest degree of all terms is 3+1=4);

3. is a polynomial of 2th degree (the highest degree of all terms is 2);

4. is not a polynomial, because the degree of second term is a fraction ;

5. is a monomial with 1st degree;

6. is not a polynomial, because here the variable x is placed in degree.

He na a