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Show that 2x + 1 is a factor of


{2x}^(3) - {x}^(2) + 3x + 2


PLS HELP ​

1 Answer

2 votes

Explanation:

First, simply


2x + 1 = x + 0.5

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


x + 0.5

Which can be written as


x - ( - 0.5)

So our a is -0.5, when then plug that in the polynomial.


2( - 0.5) {}^(3) - ( - 0.5) {}^(2) + 3( - 0.5) + 2


2( - 0.125) - (0.25) - 1.5 + 2


- 0.25 - 0.25 - 1.5 + 2


- 0.5 - 1.5 + 2


- 2 + 2 =


0

Since that satires the remainder Theorem, 2x+1 is a factor of the polynomial.

User James Messinger
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