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And when f(x) is divided by (2x-k) I have -8

How do i find values for k?

- Thread starter chris_tams
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- #1

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And when f(x) is divided by (2x-k) I have -8

How do i find values for k?

- #2

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[tex]\frac{2x^3+7x-3}{2x-k}=-8[/tex]

and you wish to solve for k as a function of x?

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Gokul43201

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matt grime

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2x^3+7x-3 = (2x-k)(x^2+ax+b)-8

what is k?

It's a division algorithm for polynomials question; by comparing coeffs on each side you ought to be able to solve a set of simulatneous equations to find k (and a and b)

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Gokul43201

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I'm assuming you mean the remainder is -8. It's not clear, and evidently, TALewis has interpreted differently.

And Matt's way is much easier.

And Matt's way is much easier.

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Ah, if you mean the remainder is -8, that makes much more sense.

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yes, what i mean is that when, 2x^3+7x-3/(2x-k) This equals some polynomial funtion with a remainder of -8. How do i work out what the polynomial is?????????

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- #8

Gokul43201

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Expand the RHS and equate coefficients of the different powers of x, between the LHS and RHS. For instance, "Is there an x^2 term in the LHS ?...No !" So you equate the coefficient in the RHS to zero...and so on. Solving from these equations gives you k.

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Yes youth. Cheers !

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