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    Given that y=(3x-7)^5 +5(3x-7)^4, show that dy/dx=45(3x-7)^3(x-1)

    When i differentiated the original equation, i got:
    dy/dx=15(3x-7)^4 + 60(3x-7)^3
    I assume i have to simply this but i'm unsure how. So far, i have tried making dy/dx=0 and taking away 60(3x-7)^3, but this doesn't seem to work?
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    (Original post by Chelsea12345)
    Given that y=(3x-7)^5 +5(3x-7)^4, show that dy/dx=45(3x-7)^3(x-1)

    When i differentiated the original equation, i got:
    dy/dx=15(3x-7)^4 + 60(3x-7)^3
    I assume i have to simply this but i'm unsure how. So far, i have tried making dy/dx=0 and taking away 60(3x-7)^3, but this doesn't seem to work?
    Although it is good that you have tried something (seriously, not in a patronising way) setting the equation to 0 isn't justified by any info given in the question.

    Notice that a + b has turned into one term - which would be your hint that the question wants you to f _ _ _ _ _ _ _ e and then simplify it.
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    (Original post by Kevin De Bruyne)
    Although it is good that you have tried something (seriously, not in a patronising way) setting the equation to 0 isn't justified by any info given in the question.

    Notice that a + b has turned into one term - which would be your hint that the question wants you to f _ _ _ _ _ _ _ e and then simplify it.
    is there meant to be a space there? or is the word not appearing?
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    (Original post by Chelsea12345)
    is there meant to be a space there? or is the word not appearing?
    he is trying not to give you too much help:

    F _ _ _ O _ _ _ E
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    (Original post by the bear)
    he is trying not to give you too much help:

    F _ _ _ O _ _ _ E
    Is there a C in there? :beard:
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    (Original post by RDKGames)
    Is there a C in there? :beard:
    F _ C _ O _ _ _ E

    next !!
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    (Original post by Chelsea12345)
    Given that y=(3x-7)^5 +5(3x-7)^4, show that dy/dx=45(3x-7)^3(x-1)

    When i differentiated the original equation, i got:
    dy/dx=15(3x-7)^4 + 60(3x-7)^3
    I assume i have to simply this but i'm unsure how. So far, i have tried making dy/dx=0 and taking away 60(3x-7)^3, but this doesn't seem to work?
    What if I tell you that if we let a=3x-7 then our expression for y' is simply 15a^4+60a^3, which can be simplified by....?
 
 
 
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