Question

Which are polynomials

Answer 1

Given:

Given that there are 4 expressions.

We need to determine the expressions that are polynomials.

Option a: $-7x^2+\frac{5}{3x}$

In the second term of the expression, the constant is divided by a variable.

For an expression to be a polynomial, it should not divided by a variable.

Hence, the expression $-7x^2+\frac{5}{3x}$ is not a polynomial.

Thus, Option a is not the correct answer.

Option b: $-x^{2}+5 x$

The given expression satisfies the conditions of the polynomial.

Hence, the expression $-x^{2}+5 x$ is a polynomial.

Thus, Option b is the correct answer.

Option c: $6 x^{2}+5 x$

The given expression satisfies the conditions of the polynomial.

Hence, the expression $6 x^{2}+5 x$ is a polynomial.

Thus, Option c is the correct answer.

Option d: $x^{2}+5 x^{\frac{1}{5}}$

The second term of the expression contains the exponent $\frac{1}{5}$

For an expression to be a polynomial, the fractional exponent is not allowed.

Hence, the given expression $x^{2}+5 x^{\frac{1}{5}}$ is not a polynomial.

Thus, Option d is not the correct answer.