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    Could someone explain to me how the dy/dx was worked out in this question please?

    This is what I got, I don't quite understand where the dy/dx in the equation comes from.


    Thank you.
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    (Original post by Y_123456)
    Could someone explain to me how the dy/dx was worked out in this question please?

    This is what I got, I don't quite understand where the dy/dx in the equation comes from.


    Thank you.
    Whenever you differentiate a 'y' term you have to put dy/dx next to it

    For example, if you have
    y = 5x+2

    you differentiate both sides and get:

    (1)dy/dx = 5
    so dy/dx = 5
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    This is an example of IMPLICIT differentiation. in most cases you do differentiation where its something=y but in this case you cant seperate it so that something=y so you have to differentiate a different way. you use the same methods, but when differentiating a term with y in it you multiply by dy/dx. Surely youve been taught this? or are you trying to skip ahead before your class has gone over it?
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    You're using both the product rule and chain rule because your differentiating with respect to x

    Edit: sorry if I sound a bit unclear, it's just that I've only just done this topic myself

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    (Original post by GPODT)
    Whenever you differentiate a 'y' term you have to put dy/dx next to it

    For example, if you have
    y = 5x+2

    you differentiate both sides and get:

    (1)dy/dx = 5
    so dy/dx = 5
    Thank you so much! I understand it now.
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    (Original post by J1994D)
    This is an example of IMPLICIT differentiation. in most cases you do differentiation where its something=y but in this case you cant seperate it so that something=y so you have to differentiate a different way. you use the same methods, but when differentiating a term with y in it you multiply by dy/dx. Surely youve been taught this? or are you trying to skip ahead before your class has gone over it?
    Looking through the chapter before being taught. Not doing a good job am I. And thank you for explaining.
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    (Original post by SDavis123)
    You're using both the product rule and chain rule because your differentiating with respect to x

    Edit: sorry if I sound a bit unclear, it's just that I've only just done this topic myself

    Posted from TSR Mobile
    No worries. Thank you, every little helps.
 
 
 
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