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    11b) mixed exercise 5e , binomial expansion.
    By making suitable substitutions for x in your answer to part a , show that (2+sqrt3)^6 -(2-sqrt3)^6 can be simplified to the form ksqrt3
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    (Original post by Garyglitter)
    11b) mixed exercise 5e , binomial expansion.
    By making suitable substitutions for x in your answer to part a , show that (2+sqrt3)^6 -(2-sqrt3)^6 can be simplified to the form ksqrt3
    I haven't done this in years so I can't remember the binomial expansion formulae, but have you tried using "let x = sqrt3"? Rewrite the question to get (2+x)^6 - (2-x)^6, expand, gather up terms and then switch the x for sqrt 3 again.

    Hopefully that'll do it!
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    Firstly unamusing choice of name.

    Secondly there is more than one textbook for Core 2 and more than one Awarding Body.

    Thirdly you could use the difference of two squares. a^2-b^2=(a+b)(a-b) or use the binomial theorem.
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    (Original post by Garyglitter)
    11b) mixed exercise 5e , binomial expansion.
    By making suitable substitutions for x in your answer to part a , show that (2+sqrt3)^6 -(2-sqrt3)^6 can be simplified to the form ksqrt3
    Clearly you need to use part a

    It would help if you gave us part a
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    (Original post by TenOfThem)
    Clearly you need to use part a It would help if you gave us part a
    Dear Sir I may give you part a in return for help...It might get a tad bit messy but here it is:64+192x+240x^2+160x^3+60x^4+6 x^5+x^6http://www.thestudentroom.co.uk/images/smilies/eek.png
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    (Original post by Kenchmeister)
    Dear Sir I may give you part a in return for help...It might get a tad bit messy but here it is:64+192x+240x^2+160x^3+60x^4+6 x^5+x^6http://www.thestudentroom.co.uk/images/smilies/eek.png
    Dear Madam

    I doubt that is the question
 
 
 
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Updated: February 14, 2013
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