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lovely maths

Discussion in 'General Discussion' started by xirokx, 7 Jun 2010.

  1. xirokx

    Mobster

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    i have two numbers i need to express in standard form, can someone tell me how?

    a) sqrt3 (so in words surd of 3)

    b) 1/5 sqrt5 (so in words 1over5 surd of 5)

    thanks
     
  2. D D Danneh

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    standard form? Sure you don't just mean index form?
     
  3. Skillmister

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    Cant be standard form with those questions im sure :eek:
     
  4. D D Danneh

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    That's what I was thinking, if it was index form though you'd be wanting:

    a) 3^1/2

    b) 1/5 5^1/2
     
  5. Begbie

    Capodecina

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    Slowly backs out of thread
     
  6. sid

    Soldato

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    multiply top and bottom by square root to get rid of them

    Its called rationalising the denominator
     
  7. PMKeates

    Capodecina

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    How do you rationalise the denominator of sqrt(3)?
     
  8. D D Danneh

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    There is no irrational denominator to rationalise :p
     
  9. agnes

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    I wish I knew the answers, I would be earning so much money if so.

    ags
     
  10. Alex74

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    = 5^(-1/2) :o
     
  11. xirokx

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    yep i meant index form...

    sowwwwyy

    yeh so like 1.3734242x102 (10 the power of 2)
     
  12. lord filbuster

    Wise Guy

    Joined: 7 Jul 2007

    Posts: 1,406

    That is standard form.

    500 = 5x10^2
    1000 = 1x10^3 etc.

    As above, you can't write irrational numbers like sqrt(3) in standard form.

    You must want them written in index form, as the others have given you.
    sqrt(3) = 3^1/2
    1/5*sqrt(5) = 1/5*5^-1/2
     
  13. xirokx

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    can you write these using the proper symbols for me and not using words as I want to make sure I have this correct..

    pleaseeeeeeeee
     
  14. lord filbuster

    Wise Guy

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    ok, i can't work out how to do superscripts, so here is a picture:
    [​IMG]
     
  15. xirokx

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    i love u
     
  16. Killerkebab

    Sgarrista

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    The bottom one is wrong - I thought he wanted 1/5 * sqrt(5), NOT 1/5 * 1/sqrt(5) :confused:
     
  17. lord filbuster

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    Possibly, i just guessed at what he wanted. The OP is a bit ambiguous.
     
  18. xirokx

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    to clarify I need to convert both these numbers into index form, what would it be:

    a) 1/5 * sqrt(5)

    b) 7^6

    please clarify

    thanks
     
  19. Westyfield2

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    I tried to forget A-Level maths for a reason! Don't bring it all flooding back!
     
  20. xirokx

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    im sorry its my error there is no *

    the question is : simplify 1/sqrt5 and leave answer in index form

    my answer to the question which is not in index form is:

    1/5 sqrt5

    so my answer (1/5 sqrt5) now needs to be put in index form

    third time lucky :)

    thanks for your help