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    how do you differentiate

    (x+y)^3 = x^2 + y

    ( i know how to do the RHS, just not the bit in brackets)
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    Are you differentiating with respect to x or y?
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    Here is the algebraic solution by implicit differentiation:
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    (Original post by Kota Dagnino)
    Here is the algebraic solution by implicit differentiation:
    https://www.thestudentroom.co.uk/sho...0#post73059680
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    (Original post by Kota Dagnino)
    Here is the algebraic solution by implicit differentiation:
    oh i see now thanks
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    (Original post by jarjarbinkss)
    how do you differentiate

    (x+y)^3 = x^2 + y

    ( i know how to do the RHS, just not the bit in brackets)
    You can differentiate the LHS by substitution.

    Let u=x+y, then what is \dfrac{du}{dx} ?

    Then by the chain rule,
    \dfrac{d}{dx}(x+y)^3 = \dfrac{du}{dx} \dfrac{d}{du} (x+y)^3 = \dfrac{du}{dx} \cdot \dfrac{d}{du} u^3
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    (Original post by RDKGames)
    You can differentiate the LHS by substitution.

    Let u=x+y, then what is \dfrac{du}{dx} ?

    Then by the chain rule,
    \dfrac{d}{dx}(x+y)^3 = \dfrac{du}{dx} \dfrac{d}{du} (x+y)^3 = \dfrac{du}{dx} \cdot \dfrac{d}{du} u^3
    thank you
 
 
 
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