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    (Original post by _Xenon_)
    Is the other one negative? So (-2,-8)
    yes
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    (Original post by Zacken)
    Yep! Well done.
    Thanks so is the 2 really + or - 2 then the 2 coordinates are positive (2,8) and negative (-2,-8)
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    (Original post by samb1234)
    yes
    Thanks ^
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    (Original post by _Xenon_)
    Thanks so is the 2 really + or - 2 then the 2 coordinates are positive (2,8) and negative (-2,-8)
    Basically, you had the equation x^2 = 4 which has solutions x = \pm 2. The corresponding y-values are (2)^3 = 8 and (-2)^3 = -8.

    Hence one point is (2, 8) and the other is (-2, -8). (i.e: there are two points with the same gradient) Does that answer your question? I'm not sure what you're asking.
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    multiply by the power and reduce the power by 1
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    (Original post by thefatone)
    multiply by the power and reduce the power by 1
    ...dude, what?
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    (Original post by Zacken)
    ...dude, what?
    \dfrac{\mathrm d y}{\mathrm d x} = n\times ax^{n-1}
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    The way I learnt it was basically you multiply the multiplier of X by the power and take 1 away from the power. If there is no power then the X completely cancels out, and if there is no X, then the number completely cancels out, so 2X^3= 6X^2, x^2= 2X, -8X= -8, and 3 cancels out.
    This means that dy/dx=6X^2+2X-8
    I don't really get why it works, I just know that's what you do XD
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    (Original post by thefatone)
    multiply by the power and reduce the power by 1
    Yes I understood that bit already I'm now trying harder examples
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    (Original post by Zacken)
    Basically, you had the equation x^2 = 4 which has solutions x = \pm 2. The corresponding y-values are (2)^3 = 8 and (-2)^3 = -8.

    Hence one point is (2, 8) and the other is (-2, -8). (i.e: there are two points with the same gradient) Does that answer your question? I'm not sure what you're asking.
    Hi yes that makes sense!
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    (Original post by _Xenon_)
    Yes I understood that bit already I'm now trying harder examples
    oh ok what about this one?

    y= \dfrac{1}{2}x^{\frac{3}{2}}
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    (Original post by _Xenon_)
    Hi yes that makes sense!
    Awesome.
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    (Original post by thefatone)
    oh ok what about this one?

    y= \dfrac{1}{2}x^{\frac{3}{2}}
    No I don't know fractions one please explain it. :-)
    EDIT: I don't think I need to know that type for my exam, not sure.
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    (Original post by _Xenon_)
    No I don't know fractions one please explain it. :-)
    EDIT: I don't think I need to know that type for my exam, not sure.
    Its exactly the same process
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    (Original post by _Xenon_)
    No I don't know fractions one please explain it. :-)
    EDIT: I don't think I need to know that type for my exam, not sure.
    oh

    multiply  \frac{1}{2}\ by\ \frac{3}{2}\ then\ reduce\ the\ power\ by\ 1
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    (Original post by samb1234)
    Its exactly the same process
    oK thanks I'll now answer the questions in my exam practise book.
    Then I need to do some Chemistry revision
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    (Original post by _Xenon_)
    oK thanks I'll now answer the questions in my exam practise book.
    Then I need to do some Chemistry revision
    Hey! I'd just like to say that you've done really well in learning this differentiation thing so far, good job!
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    (Original post by Zacken)
    Hey! I'd just like to say that you've done really well in learning this differentiation thing so far, good job!
    Thanks I think my teacher didn't teach these topics because they want the class to achieve Cs to at least pass maths and maybe some students would have struggled but I can do much better than that so I'm trying to learn these extra topics myself for maximum marks. Thanks very much for helping me with this otherwise I wouldn't have understood. I really appreciate it.

    I have an exam practise book with exam style questions for every topic on my exam so I'm just trying to learn what I don't know atm. Thanks again!
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    (Original post by _Xenon_)
    oK thanks I'll now answer the questions in my exam practise book.
    Then I need to do some Chemistry revision
    Have fun - I'm doing chem revision atm lol
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    (Original post by _Xenon_)
    Thanks I think my teacher didn't teach these topics because they want the class to achieve Cs to at least pass maths and maybe some students would have struggled but I can do much better than that so I'm trying to learn these extra topics myself for maximum marks.
    What grade are you aiming for?
 
 
 
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