Solving (b) (i) and (ii): Find Value of k and LCM of f(x) and f(x+k)

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Homework Help Overview

The problem involves the polynomial function f(x) = x^3 - 6x^2 + 3x + 10, with a focus on determining a positive integer k such that the highest common factor (HCF) of f(x) and f(x+k) is linear. The tasks include finding the value of k and the least common multiple (LCM) of f(x) and f(x+k).

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the factorization of f(x) and its implications for finding f(x+k). There is an exploration of the relationship between the factors of f(x) and the conditions for the HCF to be linear. Some participants suggest using trial and error to identify suitable values for k.

Discussion Status

The discussion is ongoing, with participants sharing their attempts at factorization and raising questions about the next steps. Some guidance has been offered regarding the relationship between the factors of f(x) and f(x+k), but no consensus has been reached on the specific values of k or the LCM.

Contextual Notes

Participants note that the problem is constrained by the requirement for k to be a positive integer and the definition of the HCF as linear. There is also a mention of the need for complete factorization of f(x) to proceed further.

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Homework Statement




given f(x) = x^3 - 6x^2 + 3x + 10

(a) Factorize f(x)
(b) if k is a positive integer such that HCF of f(x) and f(x+k) is linear.
(i) find value of k
(ii) find LCM of f(x) and f(x+k)





Homework Equations




I have no problem with (a) and f(x) = (x+1) (x^2 - 7x + 10)

I have problem with (b) (i) and (ii), I only know that HCF is linear means that there is only one factor which is linear. And that's it. I know nothing further to solve the questipn


The Attempt at a Solution

 
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kenny1999 said:

Homework Equations




I have no problem with (a) and f(x) = (x+1) (x^2 - 7x + 10)
Do you need a complete factorization? If so, you are not finished. x2 - 7x + 10 is factorable.
 
eumyang said:
Do you need a complete factorization? If so, you are not finished. x2 - 7x + 10 is factorable.

i have factored f(x) into (x+1)(x-5)(x-2)
but no idea to go further
 
kenny1999 said:
i have factored f(x) into (x+1)(x-5)(x-2)
but no idea to go further

What are the factors of f(x+k)?
 
Using the factored form of f(x), find f(x+k).

I'm assuming that HCF=GCF (greatest common factor). You are looking for a positive k such that there is a linear common factor between f(x) and f(x+k). So one of the three factors of f(x) should also be a factor of f(x+k). I used trial and error to find such a k. Find a k so that when you plug into the factored form of f(x+k), one of its factors is also a factor of f(x).


(Hope I'm not giving away too much here.)
 
eumyang said:
Using the factored form of f(x), find f(x+k).

I'm assuming that HCF=GCF (greatest common factor). You are looking for a positive k such that there is a linear common factor between f(x) and f(x+k). So one of the three factors of f(x) should also be a factor of f(x+k). I used trial and error to find such a k. Find a k so that when you plug into the factored form of f(x+k), one of its factors is also a factor of f(x).


(Hope I'm not giving away too much here.)


Yes, I think you are.
 
hi how about LCM?
 
kenny1999 said:
hi how about LCM?

Well, what about it? What work have you done on it so far?
 

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