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    hello everyone,

    so i started a question and it asked 'by expressing the left-hand side of the equation x^4-6x^3-14x^2 -6x+1=0 as the product of two quadratic factors, state the largest root of the equation.

    so first thing i did was expand it and get (x^2 - 8x +1)(x^2 + 2x+1)
    and found that

    x=-1 or 4+sqrt 15 or 4-sqrt15

    so the answer is 4+sqrt15, i want to know if I'm correct…

    thank you
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    (Original post by lilly9999)
    so the answer is 4+sqrt15, i want to know if I'm correct…

    thank you
    http://www.wolframalpha.com/input/?i...%3D0&t=crmtb01
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    oh great! thank you i just wanted to double check
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    The probability of a telephone salesperson being female is 0.7
    The probability of a female telephone salesperson using a mobile phone is 0.2
    The probability of a male telephone salesperson using a mobile phone is 0.15
    What is the probability that a telephone sales call is made on a mobile phone?
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    (Original post by KarlLynagh)
    The probability of a telephone salesperson being female is 0.7
    The probability of a female telephone salesperson using a mobile phone is 0.2
    The probability of a male telephone salesperson using a mobile phone is 0.15
    What is the probability that a telephone sales call is made on a mobile phone?
    have you drawn a tree diagram yet ?
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    yes and i got an answer of 0.185
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    (Original post by KarlLynagh)
    yes and i got an answer of 0.185
    That is correct
 
 
 
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