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Is x – 4 a factor of P(x) = x^4 - 4x^2 – 4x + 8 ? Explain.​

User JeremyKun
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1 Answer

6 votes

Answer:

(x3 - 2x2 - 4) • (x + 2)

Explanation:

STEP

1

:

Equation at the end of step 1

(((x4) - 22x2) - 4x) - 8

STEP

2

:

Checking for a perfect cube

2.1 x4-4x2-4x-8 is not a perfect cube

Trying to factor by pulling out :

2.2 Factoring: x4-4x2-4x-8

Thoughtfully split the expression at hand into groups, each group having two terms :

Group 1: x4-8

Group 2: -4x2-4x

Pull out from each group separately :

Group 1: (x4-8) • (1)

Group 2: (x+1) • (-4x)

Polynomial Roots Calculator :

2.3 Find roots (zeroes) of : F(x) = x4-4x2-4x-8

Polynomial Roots Calculator is a set of methods aimed at finding values of x for which F(x)=0

Rational Roots Test is one of the above mentioned tools. It would only find Rational Roots that is numbers x which can be expressed as the quotient of two integers

The Rational Root Theorem states that if a polynomial zeroes for a rational number P/Q then P is a factor of the Trailing Constant and Q is a factor of the Leading Coefficient

In this case, the Leading Coefficient is 1 and the Trailing Constant is -8.

The factor(s) are:

of the Leading Coefficient : 1

of the Trailing Constant : 1 ,2 ,4 ,8

User Nick Foden
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