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    I can't remember anything from GCSE or core 123 how is question 1 done? Tried the sine rule but ended up with sin(angle) =1.5 which ain't possible
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    (Original post by oinkk)
    Hey! Which part don't you understand?

    Personally, I went with the first alternative in the mark scheme:
    1. Isolate z in the transformation
    2. Let z = x + iy, let w = u + iv, then let v = -1 as required
    3. Simplify down to have Re + Im = Re + Im on both sides
    4. Solve to find y (hint: on both sides of the equation, the real parts must be equal and the imaginary parts must be equal).
    Thank you so much! I completely forgot I had to equate the imaginary part on one side to the imaginary part on the other side.
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    (Original post by Rkai01)
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    I can't remember anything from GCSE or core 123 how is question 1 done? Tried the sine rule but ended up with sin(angle) =1.5 which ain't possible
    Use cosine forumla (rearrange for bsquared), then use 1/2abSinC
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    (Original post by Rkai01)
    No that's correct. Why did it shuffle down to that expression?
    In series expansions adding more terms results in a more accurate answer as long as your x value is in the range and preferably close to your focus point. The different ranges are in the formula booklet. Here the questions asks only for an estimate to 3dp and the values you're integrating between are close to pi/4. Therefore you only need to use the first two terms of the series expansion you got from part (a) as they would give you a good enough estimate. The real value to 3dp is 0.093 and my estimate is 0.092 so I would say that's pretty good. I hope you understand. If you have the Edexcel FP2 textbook they explain quite well in the Maclaurin and Taylor series section.
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    (Original post by ddbrain)
    Thank you so much! I completely forgot I had to equate the imaginary part on one side to the imaginary part on the other side.
    Can I ask what the answer to the question was ?
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    Can any type of questions from IAL or the older adapted papers come up?
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    (Original post by ddbrain)
    Hi guys, I don't understand question 6a of June 2014 R. I've looked at the mark scheme but I still don't get it. Could someone show me the working please? I would be extremely grateful

    Attachment 543717
    Let W=u+iv and z=x+iy. Simplify the RHS stuff and separate the real and imaginary parts. Now, we know u= 'the real part' and v='the imaginary part', but we also know v=-1, so let the imaginary part = -1. Something should fall out to give you a line in x and y
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    (Original post by Rkai01)
    Attachment 543177Attachment 543177543179
    For 11b how is it done? I could see a pattern but then I could only see of making x=0 not 2 and then wasn't sure what to do with the r
    do you have the solutions to these ?
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    (Original post by moonlight123)
    Can any type of questions from IAL or the older adapted papers come up?
    I dont think they're any different .. am i missing something?
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    (Original post by target21859)
    In series expansions adding more terms results in a more accurate answer as long as your x value is in the range and preferably close to your focus point. The different ranges are in the formula booklet. Here the questions asks only for an estimate to 3dp and the values you're integrating between are close to pi/4. Therefore you only need to use the first two terms of the series expansion you got from part (a) as they would give you a good enough estimate. The real value to 3dp is 0.093 and my estimate is 0.092 so I would say that's pretty good. I hope you understand. If you have the Edexcel FP2 textbook they explain quite well in the Maclaurin and Taylor series section.
    So you ignored the squared term since limits of x are close to pi/4 and we are told that as powers increase they become less significant and so can be ignored? where (x-a) and a is approx x.
    I think I saw that in a book.
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    (Original post by moonlight123)
    Can any type of questions from IAL or the older adapted papers come up?
    Yeh the spec is exactly the same.


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    Name:  image.jpg
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Size:  501.4 KB Hey, can someone help me ? I have no idea how to get from the top line to the bottom.. I have the correct answer because I looked at the MS but have no idea why it is correct or how..
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    (Original post by Rkai01)
    So you ignored the squared term since limits of x are close to pi/4 and we are told that as powers increase they become less significant and so can be ignored? where (x-a) and a is approx x.
    I think I saw that in a book.
    That's correct but for this question I ignored the squared terms mainly because it asked for an estimation and if I kept the the x^2 term the integration wouldn't have been very nice. That question would be probably be a 2 or 3 marker and doing the integral with the squared terms included would be worth a lot more marks and isn't even on the FP2 spec. If in our fp2 exam there's a question like this they will expect you to see that using the squared terms would lead to a nasty integration and therefore not use it hence the estimation.
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    (Original post by moonlight123)
    Use cosine forumla (rearrange for bsquared), then use 1/2abSinC
    I let the Unknown side equal b and 3 equal c etc and end up with a quad in b but it solves to give imaginary numbers?
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    (Original post by wr123)
    Name:  image.jpg
Views: 131
Size:  501.4 KB Hey, can someone help me ? I have no idea how to get from the top line to the bottom.. I have the correct answer because I looked at the MS but have no idea why it is correct or how..
    Just differentiate it basically and use C4 to implicate it.
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    (Original post by wr123)
    Name:  image.jpg
Views: 131
Size:  501.4 KB Hey, can someone help me ? I have no idea how to get from the top line to the bottom.. I have the correct answer because I looked at the MS but have no idea why it is correct or how..
    Hope this explains it to you. I tried to do in as many steps as possible. Sorry for he bad handwriting Name:  image.jpg
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    (Original post by Rkai01)
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    Just differentiate it basically and use C4 to implicate it.
    (Original post by target21859)
    Hope this explains it to you. I tried to do in as many steps as possible. Sorry for he bad handwriting Name:  image.jpg
Views: 122
Size:  512.4 KB
    Thank you both very much !! You are both amazing haha
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    (Original post by target21859)
    In series expansions adding more terms results in a more accurate answer as long as your x value is in the range and preferably close to your focus point. The different ranges are in the formula booklet. Here the questions asks only for an estimate to 3dp and the values you're integrating between are close to pi/4. Therefore you only need to use the first two terms of the series expansion you got from part (a) as they would give you a good enough estimate. The real value to 3dp is 0.093 and my estimate is 0.092 so I would say that's pretty good. I hope you understand. If you have the Edexcel FP2 textbook they explain quite well in the Maclaurin and Taylor series section.
    Please could you tell me what page it's explained on in the textbook please so I can have a read, thanks
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    (Original post by Zacken)
    Put up an example and explain your reasoning.

    https://8dedc505ac3fba908c50836f5905...%20Edexcel.pdf

    Q8 I'm just not sure what limits of integration to use... I was thinking pi/2 and pi/3 which was correct but I was uncertain when I chose it. That's a easier one but like on the more complex one I get even more confused lol, what so the angle it makes when the two points intersect on any q in general are the two angles I pick for my integration limits?
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    (Original post by economicss)
    Please could you tell me what page it's explained on in the textbook please so I can have a read, thanks
    P110 in yellow text boxes in top right corner
 
 
 
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