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    The question i'm struggling with is 'Find the value of k if the remainder when x^3+4x^2+kx+3 is divided by 3x-2 is 5.' Could anyone tell me the answer (and possibly their workings)? Thanks
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    Using the remainder theorem, f(2/3)=5 where f(x)=x^3+4x^2+kx+3. Use this information to solve for k.
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    (Original post by rachelbutler)
    The question i'm struggling with is 'Find the value of k if the remainder when x^3+4x^2+kx+3 is divided by 3x-2 is 5.' Could anyone tell me the answer (and possibly their workings)? Thanks
    Do you know how the remainder theorem works?
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    Oh okay, so do you just substitute 2/3 in and put it =5 and rearrange to find k?
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    (Original post by rachelbutler)
    Oh okay, so do you just substitute 2/3 in and put it =5 and rearrange to find k?
    Do you understand why you need to do this
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    sort of.. you know there's a remainder of 5 so when you divide by 3x-2 it has to =5.
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    (Original post by rachelbutler)
    sort of.. you know there's a remainder of 5 so when you divide by 3x-2 it has to =5.
    Hmmmm

    Do you know why you are using 2/3
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    not entirely, something to do with 3x-2=0 and finding that x=2/3
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    (Original post by rachelbutler)
    not entirely, something to do with 3x-2=0 and finding that x=2/3
    Yes, that is why
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    okay, thank you for your help! It is appreciated
 
 
 
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