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    https://www.youtube.com/watch?time_c...&v=twH9iZbXyKU

    When proving this, why did he use the equation he's trying to prove for the Kth term and the other equation for (K+1)? thanks
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    (Original post by Maths&physics)
    https://www.youtube.com/watch?time_c...&v=twH9iZbXyKU

    Its ok, I got help with that last question, thanks. When proving this, why did he use the equation he's trying ti prove for the Kth term and the other equation for (K+1)? thanks

    Because that's how induction works.

    He assumed that the proposition, which is u_n=2n^2-4n+6-2^{-n}, to be TRUE for n=k.

    This clearly means that we now have u_k=2k^2-4k+6-2^{-k} as a TRUE relation that we can use.


    When you move onto n=k+1, you need to start with recurrence relation, so when writing down u_{k+1} you need to use the recurrence relation. The key part is then using the inductive assumption and put it INSIDE the first relation, and simplify to show the second relation is true for n=k+1. So you need to work with both - it's a basic principle of induction.
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    (Original post by RDKGames)
    Because that's how induction works.

    He assumed that the proposition, which is u_n=2n^2-4n+6-2^{-n}, to be TRUE for n=k.

    This clearly means that we now have u_k=2k^2-4k+6-2^{-k} as a TRUE relation that we can use.


    When you move onto n=k+1, you need to start with recurrence relation, so when writing down u_{k+1} you need to use the recurrence relation. The key part is then using the inductive assumption and put it INSIDE the first relation, and simplify to show the second relation is true for n=k+1. So you need to work with both - it's a basic principle of induction.
    thanks
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    Notnek bit of a disaster with the moving of posts here, now I'm the thread starter since I posted the response before he made this thread. Fix pls

    (Original post by Maths&physics)
    thanks
    Best if you just create new threads with appropriate titles corresponding to your topic question whenever you need to ask something.
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    (Original post by RDKGames)
    Notnek bit of a disaster with the moving of posts here, now I'm the thread starter since I posted the response before he made this thread. Fix pls



    Best if you just create new threads with appropriate titles corresponding to your topic question whenever you need to ask something.
    I will do. thanks again
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    (Original post by RDKGames)
    Notnek bit of a disaster with the moving of posts here, now I'm the thread starter since I posted the response before he made this thread. Fix pls
    I just changed the time of your post and that's fixed it.
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    (Original post by Notnek)
    I just changed the time of your post and that's fixed it.
    Didn't even know that was a thing mods can do lol
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    (Original post by RDKGames)
    Didn't even know that was a thing mods can do lol
    its ok. I got it.
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    (Original post by RDKGames)
    Didn't even know that was a thing mods can do lol
    It's not something we're meant to do regularly. But it can be tempting to bump threads by changing the post time
 
 
 
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