Which of the following is not a polynomial?
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For this case we have the following:
So:
[tex]x ^ 2 + x^{\frac{1}{2} }+ x + 6[/tex] is not a polynomial
Answer:
Option B
The expression which is not a polynomial is:
B) [tex]x^2+x^{\dfrac{1}{2}}+x+6[/tex]
We know that the general form of a polynomial expression is given by:
[tex]P(x)=a_nx^n+a_{n-1}x^{n-1}+a_{n-2}x^{n-2}+......+a_2x^2+a_1x+a_0[/tex]
i.e. P(x) is a polynomial of degree n , where n belongs to natural numbers and [tex]a_i's[/tex] belong to the real numbers.
and [tex]a_n\neq 0[/tex]
A)
[tex]\dfrac{3}{x^{-1}}+\dfrac{3}{2}[/tex]
which could also be written by:
[tex]3x+\dfrac{3}{2}[/tex]
Hence, this expression is a polynomial expression.
Option: a is incorrect.
B)
[tex]x^2+x^{\dfrac{1}{2}}+x+6[/tex]
Since in the second term the power of x does not belong to the set of natural numbers.
Hence, option: b is not a polynomial expression.
Hence, the correct answer is option: b
C)
[tex]x^3-9[/tex]
Since, the expression matches the definition of the polynomial expression.
Hence, option: c is incorrect.
D)
[tex]\sqrt{16x^4}[/tex]
This could also be written as:
[tex]=4x^2[/tex]
Hence, it is a polynomial expression.
Hence, option: d is incorrect.