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    1)Solve the equation - modulus(x) + sqrt(x+4) - 2=0
    Also I have another question which in 'Essential Maths for Economic Analysis' is 2.2.4, and it is the one with K,L, r and w as varaibles/parameters. I have to find K(L).

    Any help would be appreciated, as I am really struggling with this module.

    Thanks,

    Paul
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    Square everything perhaps?
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    I've tried that, but then go to use the quadratic formula and get a negative discriminant
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    Have you studied complex numbers?
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    I am not sure, I have studied the modulus before. I have MEI A level maths at an A grade.
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    (Original post by paul_blakeman)
    I am not sure, I have studied the modulus before. I have MEI A level maths at an A grade.
    What did you get for the discriminant?
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    (Original post by xCBRx)
    What did you get for the discriminant?
    (1-(4x1x8)) = -31
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    (Original post by paul_blakeman)
    (1-(4x1x8)) = -31
    That seems like you've squared each term seperately, which you can't do. If you want to square it to get rid of the square root:

    Modulus(x) + Sqrt(x + 4) - 2 = 0
    Sqrt(x + 4) = 2 - Modulus(x)

    Then square it

    x + 4 = 4 - 4Modulus(x) + x^2

    and then work it out from there. I haven't done much with the modulus function, but I would assume that Modulus(x)^2 = x^2, as x^2 always positive?
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    Yeah thanks for your help.

    Have repped
 
 
 
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