1. `2x^2+3x+1`, find Determine expression (function) is a polynomial or not

Solution:
The Given Polynomial `=2x^2+3x+1`

`2x^2+3x+1` is a polynomial

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2. `x^(-5/2)+2x+1`, find Determine expression (function) is a polynomial or not

Solution:
The Given Polynomial `=x^(-5/2)+2x+1`

`=2x+1+1/(x^(5/2))`

In `1/(x^(5/2))` power is `(-5)/2`, is negative

`2x+1+1/(x^(5/2))` is not a polynomial

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3. `x+1/x`, find Determine expression (function) is a polynomial or not

Solution:
The Given Polynomial `=(x+1)/(x)`

`=1+1/x`

In `1/x` power is `-1`, is negative

`1+1/x` is not a polynomial

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4. `3x^2+6x-1+sinx`, find Determine expression (function) is a polynomial or not

Solution:
The Given Polynomial `=3x^2+6x-1+sinx`

`=3x^2+6x+sin(x)-1`

sin function exists
`3x^2+6x+sin(x)-1` is not a polynomial

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5. `3x^2+6x-1+sqrt(x)`, find Determine expression (function) is a polynomial or not

Solution:
The Given Polynomial `=3x^2+6x-1+sqrt(x)`

`=3x^2+6x+sqrt(x)-1`

In `sqrt(x)` power is `1/2`, is not integer

`3x^2+6x+sqrt(x)-1` is not a polynomial

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