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    (Original post by DJMayes)
    Draw the graphs. If the line is below the curve then you do the area underneath the curve minus the area underneath the line and if the line is above the curve, you do the opposite.
    Although it isn't always the case with area. Like some require trapeziums + an integrated area or something...

    I don't understand why you wouldn't know which bit to subtract, surely a negative value would deter you from it?
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    (Original post by Robbie242)
    Oh so by ''the curve'' would it mean the part which it turns (the turning point/minimum/maximum), in one case here it says the line y=12 and y=x(4+x) so am I right in saying the line would be on top?
    Yes, the line would be on top. My integration is a little rusty so I'm not sure whether you'd have to split it in 3 like this: Name:  graph.png
Views: 90
Size:  14.9 KB. Then calculate the two ends and add on the rectangle.
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    (Original post by reubenkinara)
    Yes, the line would be on top. My integration is a little rusty so I'm not sure whether you'd have to split it in 3 like this: Name:  graph.png
Views: 90
Size:  14.9 KB. Then calculate the two ends and add on the rectangle.
    Ah thanks cheers Reuben +1
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    (Original post by L'Evil Fish)
    Although it isn't always the case with area. Like some require trapeziums + an integrated area or something...

    I don't understand why you wouldn't know which bit to subtract, surely a negative value would deter you from it?
    That's true, but it's nicer to know which way round you're supposed to do it in the first place, and that isn't necessarily obvious unless you have some knowledge of the nature of the function you're integrating, which is why sketching is always useful.
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    (Original post by DJMayes)
    That's true, but it's nicer to know which way round you're supposed to do it in the first place, and that isn't necessarily obvious unless you have some knowledge of the nature of the function you're integrating, which is why sketching is always useful.
    I've realised, all WJEC papers have the graph sketched. They ask you to find co ordinates and the likes first. Then a certain shaded area so they need to supply a diagram
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    (Original post by Robbie242)
    Ah thanks cheers Reuben +1
    No worries! Did it come up in the last C2 Solomon you did?
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    Good luck with your exams everyone! I have S1 next week and I feel a lot more prepared than I was in January! Hopefully my extra preparation will pay off!


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    (Original post by ScarlettFierce)
    Good luck with your exams everyone! I have S1 next week and I feel a lot more prepared than I was in January! Hopefully my extra preparation will pay off!


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    Good luck. Is this OCR?
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    (Original post by L'Evil Fish)
    I've realised, all WJEC papers have the graph sketched. They ask you to find co ordinates and the likes first. Then a certain shaded area so they need to supply a diagram
    I think Edexcel ones usually do, but better safe than sorry. Curve sketching is an important skill anyway so they may as well start learning it early.
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    (Original post by DJMayes)
    I think Edexcel ones usually do, but better safe than sorry. Curve sketching is an important skill anyway so they may as well start learning it early.
    I think I can sketch most curves, but sometimes I have to take a few seconds to think with the fractions including xs on top and bottom, as well as trig functions (not that I'll ever need to sketch them idt)
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    (Original post by DJMayes)
    I think Edexcel ones usually do, but better safe than sorry. Curve sketching is an important skill anyway so they may as well start learning it early.
    Yep. I had a brief problem doing it in the C3 module! Thankfully with some help on here that was sorted . It was mainly the modulus stuff that got me!
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    So, I want 95+ UMS in C3.

    Any tips?

    Also, question...

    Parametric Functions, how to we find the second differential again?

    Is it differentiating dy/dx wrt to t. And dividing by dt/dx?
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    (Original post by L'Evil Fish)
    So, I want 95+ UMS in C3.

    Any tips?

    Also, question...

    Parametric Functions, how to we find the second differential again?

    Is it differentiating dy/dx wrt to t. And dividing by dt/dx?
    Do you mean how to differentiate parametric equations?
    You do \frac{dy}{dx} = \frac{dy}{dt} all over \frac{dx}{dt}
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    (Original post by jadecross)
    Do you mean how to differentiate parametric equations?
    You do \frac{dy}{dx} = \frac{dy}{dt} all over \frac{dx}{dt}
    No, as in d2y/dx2.

    Like:

    y = 3t
    x = t^2 + 2t

    dy/dx = 3 * 1/2t + 2

    = 3/(2t+2)

    d2y/dx2 = diff 3/(2t+2) wrt t and divide by dx/dt or something
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    (Original post by reubenkinara)
    Good luck. Is this OCR?
    Thank you! And Yep! Are you with OCR too?


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    (Original post by ScarlettFierce)
    Thank you! And Yep! Are you with OCR too?


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    Nope. Edexcel. I'm doing C2 when you're doing S1!
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    (Original post by L'Evil Fish)
    No, as in d2y/dx2.

    Like:

    y = 3t
    x = t^2 + 2t

    dy/dx = 3 * 1/2t + 2

    = 3/(2t+2)

    d2y/dx2 = diff 3/(2t+2) wrt t and divide by dx/dt or something
    I would 2nd differentiate your x and y then use chain rule on that.

    The only other alternate method I can see is firstly changing y in to terms of x and going from there.
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    (Original post by DashingHero)
    I would 2nd differentiate your x and y then use chain rule on that.

    The only other alternate method I can see is firstly changing y in to terms of x and going from there.
    Can you do it like that?
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    Hi, everyone, with approx 3 weeks left until the C3 & C4 exams, do you guys think that doing all the past papers from 2005 onwards is good enough preparation or not? It's not like I haven't done anything so far because I've answered some of the Qs in the book & already done a few papers here & there, I already know the content. The reason why I'm asking this is because I don't know whether I should do the Solomon papers or not, I attempted 2 of them in Easter but I found them difficult & they took me ages to finish. Also glancing at some of the past Edexcel papers, some of the Qs they contain don't seem any easier but I feel more comfortable doing them. Now I'm either thinking about just sticking with completing the Edexcel past papers or completing the Edexcel past papers & then doing some of the Solomon papers after. So overall, are the Solomon papers important?
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    Just did Jan 13 S2, it was a little harder than the normal ones, I managed to get 71/75. Managed to somehow mess up the mosquito question part d)
 
 
 
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