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    Q: This diagram represents a rectangular sheet of metal 8 cm by 5 cm. Equal squares of side x cm are removed from each corner, and the edges are then turned up to make an open box of volume v cm^3. Show that v = 40x - 26x^2 + 4x^3
    Hence find the maximum possible volume, and the corresponding value of x.

    Help would really be appreciated
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    (Original post by TarotOfMagic)
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    huh? :confused:
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    (Original post by TarotOfMagic)
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    Q: This diagram represents a rectangular sheet of metal 8 cm by 5 cm. Equal squares of side x cm are removed from each corner, and the edges are then turned up to make an open box of volume v cm^3. Show that v = 40x - 26x^2 + 4x^3
    Hence find the maximum possible volume, and the corresponding value of x.

    Help would really be appreciated
    For the first bit, can you see that the lengths of the sides will now be 8-2x and 5-2x? Then the height will be x. Multiplying these together will give you the volume
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    (Original post by TarotOfMagic)
    Name:  image.jpg
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    Q: This diagram represents a rectangular sheet of metal 8 cm by 5 cm. Equal squares of side x cm are removed from each corner, and the edges are then turned up to make an open box of volume v cm^3. Show that v = 40x - 26x^2 + 4x^3
    Hence find the maximum possible volume, and the corresponding value of x.

    Help would really be appreciated
    wow what a question

    did you try draw the net? is it possible for you to post an attempt?

    Edit: too slow
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    (Original post by DylanJ42)
    huh? :confused:
    Sorry, I accidently submitted it without writing the question: I have edited it now.
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    (Original post by TarotOfMagic)
    Sorry, I accidently submitted it without writing the question: I have edited it now.
    how are you getting on with it?
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    (Original post by tinkerbella~)
    For the first bit, can you see that the lengths of the sides will now be 8-2x and 5-2x? Then the height will be x. Multiplying these together will give you the volume
    Thanks so much! I have solved the question correctly.
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    (Original post by TarotOfMagic)
    Thanks so much! I have solved the question correctly.
    Awesome! No problem
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    (Original post by tinkerbella~)
    Awesome! No problem
    Are you the maths fairy
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    (Original post by Zacken)
    Are you the maths fairy
    No that's you dear
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    (Original post by tinkerbella~)
    No that's you dear
    I am the maths fairy
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    (Original post by Zacken)
    I am the maths fairy
    If I leave math questions under my pillow, do I get money?


    Posted from TSR Mobile
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    (Original post by drandy76)
    If I leave math questions under my pillow, do I get money?


    Posted from TSR Mobile
    You get £e^{i\pi} for every maths problem.
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    (Original post by Zacken)
    You get £e^{i\pi} for every maths problem.
    How does one get negative money :confused:?
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    (Original post by zetamcfc)
    How does one get negative money :confused:?
    I'd be stealing it from him, that was the point. Vector quantity and all.
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    (Original post by zetamcfc)
    How does one get negative money :confused:?
    well you could go to a £9000 a year uni to learn maths for a start :laugh:

    Edit: missed the joke too
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    (Original post by Zacken)
    I'd be stealing it from him, that was the point. Vector quantity and all.
    I see... getting quite late... brain not working well...
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    (Original post by drandy76)
    If I leave math questions under my pillow, do I get money?


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    if you leave money under your pillow you get a maths problem
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    (Original post by Zacken)
    I'd be stealing it from him, that was the point. Vector quantity and all.
    My money is kept in 5 dimensional space, your 3rd dimensional translations have no chance


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    (Original post by DylanJ42)
    well you could go to a £9000 a year uni to learn maths for a start :laugh:
    I have.......:cry:
 
 
 
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