Answer:
The following expressions are polynomials:
![3x^2-5x^4+2x-12](https://tex.z-dn.net/?f=3x%5E2-5x%5E4%2B2x-12)
![x^5-5x^4+4x^3-3x^2+2x-1](https://tex.z-dn.net/?f=x%5E5-5x%5E4%2B4x%5E3-3x%5E2%2B2x-1)
![x^3-7x^2+9x-5x^4-20](https://tex.z-dn.net/?f=x%5E3-7x%5E2%2B9x-5x%5E4-20)
The following expressions are not polynomials:
![\frac{4}{x^4}+\frac{3}{x^3}-\frac{2}{x^2}-1](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7Bx%5E4%7D%2B%5Cfrac%7B3%7D%7Bx%5E3%7D-%5Cfrac%7B2%7D%7Bx%5E2%7D-1)
![x^{-5}-5x^{-4}+4x^{-3}-3x^{-2}+2x^{-1}-1](https://tex.z-dn.net/?f=x%5E%7B-5%7D-5x%5E%7B-4%7D%2B4x%5E%7B-3%7D-3x%5E%7B-2%7D%2B2x%5E%7B-1%7D-1)
![\sqrt[4]{x}-\sqrt[3]{x}+4\sqrt{x}-8x+16](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7Bx%7D-%5Csqrt%5B3%5D%7Bx%7D%2B4%5Csqrt%7Bx%7D-8x%2B16)
Step-by-step explanation:
We are required to differentiate the expressions as polynomials and non-polynomials.
Since, we know,
A polynomial is an expression that involves variables and their coefficients separated by mathematical operations with the variables having non-negative integer values.
i.e. A polynomial is of the form,
, with 'n' being non-negative integer.
Thus, according to the definition, we have that,
The following expressions are polynomials:
![3x^2-5x^4+2x-12](https://tex.z-dn.net/?f=3x%5E2-5x%5E4%2B2x-12)
![x^5-5x^4+4x^3-3x^2+2x-1](https://tex.z-dn.net/?f=x%5E5-5x%5E4%2B4x%5E3-3x%5E2%2B2x-1)
![x^3-7x^2+9x-5x^4-20](https://tex.z-dn.net/?f=x%5E3-7x%5E2%2B9x-5x%5E4-20)
The following expressions are not polynomials:
![\frac{4}{x^4}+\frac{3}{x^3}-\frac{2}{x^2}-1](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7Bx%5E4%7D%2B%5Cfrac%7B3%7D%7Bx%5E3%7D-%5Cfrac%7B2%7D%7Bx%5E2%7D-1)
![x^{-5}-5x^{-4}+4x^{-3}-3x^{-2}+2x^{-1}-1](https://tex.z-dn.net/?f=x%5E%7B-5%7D-5x%5E%7B-4%7D%2B4x%5E%7B-3%7D-3x%5E%7B-2%7D%2B2x%5E%7B-1%7D-1)
![\sqrt[4]{x}-\sqrt[3]{x}+4\sqrt{x}-8x+16](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7Bx%7D-%5Csqrt%5B3%5D%7Bx%7D%2B4%5Csqrt%7Bx%7D-8x%2B16)