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    Can someone help me with these questions?

    1) find dy/dx of the following equations:

    A) xy = sin^2 (y)
    B) tan(2x+y) = x
    C) e^(xy) = 4
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    (Original post by Improvement)
    Can someone help me with these questions?

    1) find dy/dx of the following equations:

    A) xy = sin^2 (y)
    B) tan(2x+y) = x
    C) e^(xy) = 4
    Have you studied implicit differentiation? What have you tried so far?
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    I would suggest over viewing implicit differentiation where you differentiate y within the equation, as in not separated on one side. Then apply the respective rules for differentiating.

    Alternatively you could try and differentiate with respect to y and see where that takes you.
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    Yeah I completely forgot about that, I have the answer to the first and second one but for the middle one i get sec^2 instead of cos^2?
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    (Original post by Improvement)
    Yeah I completely forgot about that, I have the answer to the first and second one but for the middle one i get sec^2 instead of cos^2?
    Can you post your working and answer?
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    (Original post by Improvement)
    Can someone help me with these questions?

    1) find dy/dx of the following equations:

    A) xy = sin^2 (y)
    B) tan(2x+y) = x
    C) e^(xy) = 4
    Look up implicit differnetation and then post your workings with answers
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    B) gives sec^2(2x+y)*(2+dy/dx)=1 -> 2+dy/dx=1/sec^2(2x+y)=cos^2(2x+y) -> dy/dx = cos^2(2x+y)-2.

    (Original post by Improvement)
    Yeah I completely forgot about that, I have the answer to the first and second one but for the middle one i get sec^2 instead of cos^2?
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    (Original post by constellarknight)
    B) gives sec^2(2x+y)*(2+dy/dx)=1 -> 2+dy/dx=1/sec^2(2x+y)=cos^2(2x+y) -> dy/dx = cos^2(2x+y)-2.
    Please don't post full solutions. It's against the rules of the forum and far more beneficial to guide to a solution.
 
 
 
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