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    I tried quotient rule and regular rule but seem to get the wrong answer. Please explain how you did it.

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    (Original post by Jyashi)
    I tried quotient rule and regular rule but seem to get the wrong answer. Please explain how you did it.

    ddx[4x2+5−xx]
    I can't understand the expression
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    Do you mean 4x^2 + 5 + x^x ?
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    Sorry guys just updated with question
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    (Original post by zetamcfc)
    I can't understand the expression
    Just updated the question
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    (Original post by Jyashi)
    Just updated the question
    What is your problem with this? Differentiate the first term normally. Then quotient rule the second.
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    (Original post by Jyashi)
    Just updated the question
    No need for quotient rule: \dfrac{5-x}{x}=\dfrac{5}{x}-1=5x^{-1}-1
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    What you wrote was nothing like the question but you'd need to rearrange it so the fraction is an integer, 4x^2+ (5-x)(x^-1)
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    (Original post by joostan)
    No need for quotient rule: \dfrac{5-x}{x}=\dfrac{5}{x}-1=5x^{-1}-1
    Not really with it lol
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    I tried using chain rule and quotient rule but the answer that i need is 8x-5/x^2 which im not getting
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    (Original post by Jyashi)
    I tried using chain rule and quotient rule but the answer that i need is 8x-5/x^2 which im not getting
    Instead of telling us what you're doing, why don't you post out your working instead so we can see what you're actually doing?
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    (Original post by Zacken)
    Instead of telling us what you're doing, why don't you post out your working instead so we can see what you're actually doing?
    Its fine i managed to resolve it. But surprised that i got different answers using the chain rule and quotient rule.
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    (Original post by Jyashi)
    Its fine i managed to resolve it. But surprised that i got different answers using the chain rule and quotient rule.
    They're not different answers if you did both procedures correctly.
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    (Original post by Zacken)
    They're not different answers if you did both procedures correctly.
    Oh i am sure i messed up somewhere there. On a side note can you tell me what is the implicit derivative of ln(y) ? Do you treat y as a constant which would mean derivative of y will be 0 but then do you do 0 dy÷dx?
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    (Original post by Jyashi)
    Oh i am sure i messed up somewhere there. On a side note can you tell me what is the implicit derivative of ln(y) ? Do you treat y as a constant which would mean derivative of y will be 0 but then do you do 0 dy÷dx?
    It is (dy/dx)/y. Differentiating the logarithm of somethins is the derivative of something over the something. In this case the something is y, so d/dx(y) = dy/dx.
 
 
 
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