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    Can anyone help with this question, much appreciated if u can:

    The binomial expansion of (1+12x) ^(3/4) in ascending powers of x up to and including the term x³ is:

    1+9x+px²+px³ |12x| < 1

    a) find the value of p and the value of q

    b) use this expansion with your values of p and q together with an appropriate value of x to obtain an estimate of (1.6)^(3/4)

    c) obtain (1.6)^(3/4) from your calculator and hence make a comment on the accuracy of the estimate you obtained in part (b).
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    (Original post by madad69_81)
    Can anyone help with this question, much appreciated if u can:

    The binomial expansion of (1+12x) ^(3/4) in ascending powers of x up to and including the term x³ is:

    1+9x+px²+px³ |12x| < 1

    a) find the value of p and the value of q

    b) use this expansion with your values of p and q together with an appropriate value of x to obtain an estimate of (1.6)^(3/4)

    c) obtain (1.6)^(3/4) from your calculator and hence make a comment on the accuracy of the estimate you obtained in part (b).
    a) 1 + 9x - 27x²/2 + 134x³/2

    b) x= 0.05
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    (Original post by darth_vader05)
    we did this today :eek: for part three i think you have to use the formula - (your answer/real answer) x 100
    i doubt it's necessary. you coould just say "ooh look, it's close", or if you're really clever "ooh look, it's correct to the nth decimal place"...
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    what formula are you guys on about?
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    (Original post by gordon2002)
    what formula are you guys on about?
    calculating percentage error :cool:
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    Erm in general:

    n/r x 100, will give yo percentage difference where n is an approximation of r.

    This isn't C4, it's GCSE percentages!

    Hell it ain't even a formula, it's logic!
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    (Original post by Dekota)
    Erm in general:

    n/r x 100, will give yo percentage difference where n is an approximation of r.

    This isn't C4, it's GCSE percentages!

    Hell it ain't even a formula, it's logic!
    think you're so clever do you dekota, huh?

    well your post is incorrect. "n/r x 100, will give yo percentage difference where n is an approximation of r" won't give you the percentage difference, 1 - n/r x 100 will.

    i'm just joking :cool:
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    (Original post by Dekota)

    This isn't C4, it's GCSE percentages!

    Hell it ain't even a formula, it's logic!
    That's why I was confused about some fomula!

    yeah, so basically value of x subbed into the expanded formula divided by actual times 100?
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    (Original post by chewwy)
    think you're so clever do you dekota, huh?
    Give me 1 and 1 and I can make 3.
    i'm just joking :cool:
    Haha, What goes around, comes around. :cool:
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    on a lighter note, that was my 2000th post. woohoo.
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    (Original post by chewwy)
    on a lighter note, that was my 2000th post. woohoo.
    A mathematical response: Technically, not really since there is a 0.75 chance that you've posted in the chat forum or welcome lounge, where posts don't count. So it is likely that you've past your 2000 posts mark ages ago!

    :cool:
 
 
 
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