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    So I can do all parts of this question easily except for the last bit.

    I've found that the inequality doesn't hold true but I cant come up with a explanation as to why it doesnt.
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    (Original post by Ari Ben Canaan)
    So I can do all parts of this question easily except for the last bit.

    I've found that the inequality doesn't hold true but I cant come up with a explanation as to why it doesnt.
    You only need an explanation if it does hold true.

    Which it does!

    PS: It's an equality, not an inequality.
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    (Original post by ghostwalker)
    You only need an explanation if it does hold true.

    Which it does!

    PS: It's an equality, not an inequality.
    I did this question yesterday. I have found them to be equal. I think, looking back at my workings, I got answers of 3 in both cases.

    Why are they equal ? What is the explanation ?
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    (Original post by Ari Ben Canaan)
    I did this question yesterday. I have found them to be equal. I think, looking back at my workings, I got answers of 3 in both cases.

    Why are they equal ? What is the explanation ?
    Humm! I make it 0.

    Edit: Oops, may have misread the question - will check again.
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    (Original post by ghostwalker)
    Humm! I make it 0.

    Edit: Oops, may have misread the question - will check again.
    Just checked the mark scheme.... It says that the equality is untrue...
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    (Original post by Ari Ben Canaan)
    Just checked the mark scheme.... It says that the equality is untrue...
    Ok, Just rechecked it, and I get G'(x)=3x, and F'(y)=3y.

    Unless I made a slip somewhere.

    Edit: Yep I made a slip. Doh!

    See below.
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    My inputs:



    Hope this helps. Peace.
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    (Original post by ghostwalker)
    Ok, Just rechecked it, and I get G'(x)=3x, and F'(y)=3y.

    Unless I made a slip somewhere.
    I'd imagine the easiest way to check that you've made a slip up here is to consider the anti-symmetry of f in x and y.
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    (Original post by Farhan.Hanif93)
    I'd imagine the easiest way to check that you've made a slip up here is to consider the anti-symmetry of f in x and y.

    (Original post by WhiteGroupMaths)
    My inputs:



    Hope this helps. Peace.
    (Original post by ghostwalker)
    Ok, Just rechecked it, and I get G'(x)=3x, and F'(y)=3y.

    Unless I made a slip somewhere.

    Edit: Yep I made a slip. Doh!

    See below.
    Seems I made a negative sign vanish in my workings hence the reason why I initially believed the equality was true.

    What is the explanation for why they should or should not be equal ? This is just for my own knowledge.
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    You could try pondering over things in the geometrical context.

    I wrote this for my advanced math students ages ago, perhaps it might give you some inspiration;

    Partial Differentiation 1

    Peace.
 
 
 
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