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    \int\limits_1^3 x^3\, \mathrm\bigtriangleup x
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    (Original post by Dopey')
    \int\limits_1^3 x^3\, \mathrm\bigtriangleup x
    I think I can truthfully say that I have never in my life seen it used like that. Why?
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    (Original post by Smaug123)
    I think I can truthfully say that I have never in my life seen it used like that. Why?
    haha just curious as ive seen it as  \dfrac {\bigtriangleup x}{\bigtriangleup y}
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    Personally I don't see much wrong with it, although I've never seen it been used like that before.

    \dfrac{\Delta y}{\Delta x} = \dfrac{\delta y}{\delta x} = \dfrac{dy}{dx}

    They're all the same thing.
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    (Original post by Dopey')
    haha just curious as ive seen it as  \dfrac {\bigtriangleup x}{\bigtriangleup y}
    It's usually:
    \dfrac{\Delta y}{\Delta x}
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    (Original post by joostan)
    It's usually:
    \dfrac{\Delta y}{\Delta x}
    Can I use as I have above? on first post :/
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    (Original post by Dopey')
    Can I use as I have above? on first post :/
    Why would you want to, it takes more time to draw a triangle than to write a d? You'd just be wasting time in exams etc.
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    (Original post by hoodboilu4)
    Personally I don't see much wrong with it, although I've never seen it been used like that before.

    \dfrac{\Delta y}{\Delta x} = \dfrac{\delta y}{\delta x} = \dfrac{dy}{dx}

    They're all the same thing.
    I know but it looks better lol
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    (Original post by Dopey')
    Can I use as I have above? on first post :/
    Well I see the symbol \Delta x as a big-ish change
    \delta x as a smaller change.
    and dx when the change is infinitesimally small, but it may well be the case you can interchange them.
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    (Original post by joostan)
    Well I see the symbol \Delta x as a big-ish change
    \delta x as a smaller change.
    and dx when the change is infinitesimally small, but it may well be the case you can interchange them.
    Ok, well ill think ill just stick to standard dx
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    (Original post by Dopey')
    \int\limits_1^3 x^3\, \mathrm\bigtriangleup x

    Isaac Newton here. I did not invent calculus to see this ****. Integration is taking the sum of infinitely small changes. delta x is not an infinitely small change so you can't integrate that.
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    (Original post by hoodboilu4)
    Personally I don't see much wrong with it, although I've never seen it been used like that before.

    \dfrac{\Delta y}{\Delta x} = \dfrac{\delta y}{\delta x} = \dfrac{dy}{dx}

    They're all the same thing.
    No they're not!

    the first two represent the ratio of small changes in y to small changes in x.

    The final expression is the limit of those ratios as \delta x \to 0
 
 
 
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