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C(x)=2x^3+3x^2-1 find rational zeros

User Sme
by
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1 Answer

2 votes

Answer:

1/2

Explanation:

The Rational Root Theorem says that any rational root has

1. a numerator that is a factor of the constant term

2. a denominator that is a factor of the leading coefficient (that's attached to the highest-power term)

Numerator:
\pm 1

Denominator:
\pm 2

That means there are only two possible rational roots:
\pm (1)/(2)

Try them both by plugging them into the polynomial.


2\left((1)/(2)\right)^3 + 3\left((1)/(2)\right)^2 -1= (1)/(4)+(3)/(4)-1 =0

Aha! The negative one-half value does not produce 0

User Soroushjp
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