Are expressions with fractional coefficients and variable exponents polynomials?

[gabby989062]

the directions are: determine whether each expression is a polynomial.

i got the easyones like: 12x³-2x²+0.5 is a polynomial

but i can't figure these out:

(x³/11)+(x²/8)
I don't know if the variables can be fractions but i think this could be this:
1/11x³+1/8 x² so i think it is a polynomial.

4x-2^2x+3^5x

im not sure if the variable can be the exponent

please explain how it is or is not a polynomial. thank you

 

[Moo Of Doom]

Polynomials are functions that can be expressed as $a+bx+cx^2+...+px^n$ for real numbers a,b,c,...,p.
Thus the one with fractions is a polynomial because those fractions are real numbers. The one with x in the exponent, though, can't be so written, so it's not a polynomial.

 

[gabby989062]

Polynomials are functions that can be expressed as $a+bx+cx^2+...+px^n$ for real numbers a,b,c,...,p.
Thus the one with fractions is a polynomial because those fractions are real numbers. The one with x in the exponent, though, can't be so written, so it's not a polynomial.

THANKS DUDIE! I TOTALLY GET IT KNOW! :!)