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    https://a9497d7f220e174d38d014b2b1d8...%20Edexcel.pdf

    Question 3

    how do i know that U_1 =1?
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    (Original post by thefatone)
    https://a9497d7f220e174d38d014b2b1d8...%20Edexcel.pdf

    Question 3

    how do i know that U_1 =1?
    You don't. You know that u_1=2+k
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    (Original post by nerak99)
    You don't. You know that u_1=2+k
    but you do to reach that conclusion

    look you just put in n=1 to get out of the reccurence relation what you've stated but how do i know that

    n=1???
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    Well, for a start, I would not really call this a recurrence relation. It is a formula where we are told that
    u_n=2^n+kn Hence, if n=1 u_1=2^1+k.

    Otherwise, I do not understand your question. Yes, I just put in n=1 but that is what is required here.

    It turns out that u_1=-1 anyway.
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    (Original post by nerak99)
    Well, for a start, I would not really call this a recurrence relation. It is a formula where we are told that
    u_n=2^n+kn Hence, if n=1 u_1=2^1+k.

    Otherwise, I do not understand your question. Yes, I just put in n=1 but that is what is required here.
    how do you know this where have you gotten n=1 from? why isn't n=2?
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    We are told in a) that u_1=u_3and we have used that fact.

    I think you should go off and have a rest and come back later.

    From your previous post have you not done C1 or was that agonising just about a practice paper?
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    (Original post by nerak99)
    We are told in a) that u_1=u_3and we have used that fact.

    I think you should go off and have a rest and come back later.

    From your previous post have you not done C1 or was that agonising just about a practice paper?
    that was me being super annoyed about the fact that i can't not make stupid mistakes
    yes i do need a rest but i can't afford one, i need to do more C1
    (Original post by Malandirix)
    The n is different for each term. In the case of u1 n=1
    in the case of u3 n = 3
    i see so the number below the u is the number n= ..... right thanks
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    Well that is OK. I will take your future rep award as an apology.
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    (Original post by thefatone)
    ...
    The formula says that the given relation is true for all natural n. You can plug in whatever n you want, plug in n=2 if you want. It'll just be utterly useless and a waste of your time. The only useful ones you get is from n=1 and n=3. If you can't see why that is the most useful ones to plug in, then you really do need to have a rest.
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    (Original post by Zacken)
    The formula says that the given relation is true for all natural n. You can plug in whatever n you want, plug in n=2 if you want. It'll just be utterly useless and a waste of your time. The only useful ones you get is from n=1 and n=3. If you can't see why that is the most useful ones to plug in, then you really do need to have a rest.
    i guess but it can't be helped, i've tanned out these C1 and i need to do more, i can't do less, it won't help(yes yes overworking will exhaust me etc and i may not learn anything) but then again any new format of question i come across and i do i will remember and know how to do it the next time....

    uberteknik looks like your advice was good ^-^ and other ppl say the same thing too xD
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    (Original post by thefatone)
    i guess but it can't be helped, i've tanned out these C1 and i need to do more, i can't do less, it won't help(yes yes overworking will exhaust me etc and i may not learn anything) but then again any new format of question i come across and i do i will remember and know how to do it the next time....

    uberteknik looks like your advice was good ^-^ and other ppl say the same thing too xD
    Okay.
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    (Original post by Zacken)
    Okay.
    awesome reply xD
 
 
 
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