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De Moivres -Where am I going wrong

  • 28-11-2015 01:26PM
    #1
    Take Your Pants Off
    Registered Users, Registered Users 2 Posts: 1,520 ✭✭✭


    I am doing this question and I followed the steps in the example in the book, but I am getting completely sidetracked to what they have in the soloutions.

    Anyone done this question before ? Could explain where I am going wrong please.


Comments

  • #2
    skippy1977
    Registered Users, Registered Users 2 Posts: 284 ✭✭skippy1977


    Your method is good. The mistake is in the multiplication of surds near the end. 2 to the power of a half multiplied by a half is not 5 over 4.

    You should be getting root 2 over 2.

    Check how you are getting 5/4. I think you are multiplying 2 and half by a half rather than 2 to the POWER of a half.

    Like I said the rest of the method is good.


  • #3
    skippy1977
    Registered Users, Registered Users 2 Posts: 284 ✭✭skippy1977


    Hey there what solution are they showing. It may be just in a different form to yours. Is there a 1 over root 2 in the other solution.


  • #4
    Take Your Pants Off
    Registered Users, Registered Users 2 Posts: 1,520 ✭✭✭Take Your Pants Off


    My bad. Just saw it now, theyr the same just different form and not simplified.
    Thank you skippy. Really helpful.


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