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    how do i find dy/dx of:

    (1)
    k) xcosy
    l) x^2 e^2y
    m) e^x y^2
    n) 1/y
    o) x/y^3

    (2)
    f) 2x^2 y and 5xy^2


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    What do you think the answers are? Remember that dy/dx is taking the derivative with respect to x.
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    (Original post by m:)ckel)
    What do you think the answers are? Remember that dy/dx is taking the derivative with respect to x.
    yeah i understand that
    like for example k is cosy - xsiny dy/dx
    but how/what method was used
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    (Original post by SeekerOfKnowledge)
    yeah i understand that
    like for example k is cosy - xsiny dy/dx
    but how/what method was used
    For things like that, you have to use implicit differentiation.

    For example, for x*cos(y), you have to use the product rule on it where the first function is x and the second is cos(y).

    From there, you get cos(y) + x * d/dx [cos(y)].

    For the part that is d/dx [cos(y)], you simply use the chain rule.

    -sin(y)*dy/dx - since dy/dx is the derivative of y.

    For the other questions, just follow the normal differentiation rules (especially the chain rule) and treat 'y' as a function of y whose derivative is dy/dx.
 
 
 
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