Step-by-step explanation:
First, simply
[tex]2x + 1 = x + 0.5[/tex]
This is useful because using the remainder Theorem,
If x-a is a factor of a Polynomial, P(X)., then P(a)=0.
Here the factor is
[tex]x + 0.5[/tex]
Which can be written as
[tex]x - ( - 0.5)[/tex]
So our a is -0.5, when then plug that in the polynomial.
[tex]2( - 0.5) {}^{3} - ( - 0.5) {}^{2} + 3( - 0.5) + 2[/tex]
[tex]2( - 0.125) - (0.25) - 1.5 + 2[/tex]
[tex] - 0.25 - 0.25 - 1.5 + 2[/tex]
[tex] - 0.5 - 1.5 + 2[/tex]
[tex] - 2 + 2 = [/tex]
[tex]0[/tex]
Since that satires the remainder Theorem, 2x+1 is a factor of the polynomial.