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    It's an undergrad question but I'm asking about basics

    u = V cos theta
    v = V sin theta

    V and theta are constants

    The questions require me to differentiate u and v.

    It basically asks whether du/dx + dy/dy = 0

    However I don't have x or y values so they become 0+0 =0 right?
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    They are both zero provided theta is not a function of x or y. If this is not the case, then use the chain rule: du/dx = du/d0 x d0/dx
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    (Original post by Keoje)
    It's an undergrad question but I'm asking about basics

    u = V cos theta
    v = V sin theta

    V and theta are constants

    The questions require me to differentiate u and v.

    It basically asks whether du/dx + dy/dy = 0

    However I don't have x or y values so they become 0+0 =0 right?
    Are you sure that is the question

    If it is then you have

    u and v both as constants

    So their rate of change is 0

    However, the idea of \dfrac{du}{dx} and \dfrac{dv}{dy} (I assume that was what you meant - are meaningless
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    I've taken the context out of it to simplify matters because it doesn't really matter too much. I guess part a was simpler than I thought.

    I also made the mistake in thinking part b) was the same as other similar questions hence my confusion for this as it would of asked me to find out... but fortunately it doesn't so my worries about part a) are gone

    du/dt = u * du/dx + v * du/dy

    Thanks for the help
 
 
 
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