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Use the Factor Theorem to find all real zeros for the given polynomial function and one factor. (Enter your answers as a comma-separated list.)f(x) = 4x3 − 21x2 + 35x − 18; x − 1

User Igor Ivancha
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1 Answer

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21 votes

We know that:


f(x)=(x-1)p(x),

where


p(x)=(f(x))/(x-1).

Using synthetic division, we get:


(f(x))/(x-1)=4x^2-17x+18.

Now, notice that:


4x^2-17x+18=(x-2)(4x-9).

Therefore:


4x^3-21x^2+35x-18=(x-1)(x-2)(4x-9).

Finally, we get that the zeros of the polynomial are:


x=1,x=2,x=(9)/(4).

Answer:


x=1,x=2,x=(9)/(4).

User Shigeta
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