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    Given that x = cos^2(y^2)
    find dy/dx (idk how to do fractions with latex) in terms of y
    ___________________

    What I've done is, differentiate with respect to y to get
    dx/dy = -2y*sin(y^2)

    And then can I just take the reciprocal so...?
    dy/dx = 1/(-2y*sin(y^2))

    Not sure if I'm able to do this
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    (Original post by Retsek)
    Given that x = cos^2(y^2)
    find dy/dx (idk how to do fractions with latex) in terms of y
    ___________________

    What I've done is, differentiate with respect to y to get
    dx/dy = -2y*sin(y^2)

    And then can I just take the reciprocal so...?
    dy/dx = 1/(-2y*sin(y^2))

    Not sure if I'm able to do this
    Your method is almost right. It's just that you did it for x= cos(y^2) and not x = cos^2(y^2). I would suggest doing chain rule a second time.

    Also to make fractions in latex you do \dfrac{numerator}{denominator}
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    (Original post by Retsek)
    Given that x = cos^2(y^2)
    find dy/dx (idk how to do fractions with latex) in terms of y
    ___________________

    What I've done is, differentiate with respect to y to get
    dx/dy = -2y*sin(y^2)

    And then can I just take the reciprocal so...?
    dy/dx = 1/(-2y*sin(y^2))

    Not sure if I'm able to do this
    You did a mistake in your differentiation: if [tex] x = cos²(y²) is your term, it is dy/dx=-4cos(y²) * sin(y²). If you do the reciprocal now, you get dy/dx = 1/-4cos(y²)*sin(y²).

    You have forgotten the square in cosine!
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    x
    Yeah thanks for picking up on that, awkwardly tho the error was in my typing up of a question, it's not got a cos^2 it's just cos
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    (Original post by Retsek)
    Yeah thanks for picking up on that, awkwardly tho the error was in my typing up of a question, it's not got a cos^2 it's just cos
    It was just always the typo of yours what led to the wrong term, that is nothing bad, as long as it does not happen in class test.
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    (Original post by Kallisto)
    It was just always the typo of yours what led to the wrong term, that is nothing bad, as long as it does not happen in class test.
    Bad thing is, half reading a question and getting over eager js one of my worst habits :')
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