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Math Help - Functions question

  1. #1
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    Functions question

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  2. #2
    Senior Member pankaj's Avatar
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    f(x)=xf(x)

     <br />
(x-1)f(x)=0<br />

    Put x=2,which gives f(2)=0

    Someone should prove that f(1)=0 if the answer is indeed f(1)

    Will you tell me the source of this question
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  3. #3
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    the problem is that
    f{x} = x f{x}

    so, whatever value u put for X, the inequality will never ever hold.

    lets take an example x = 2

    f{2} = 2* f{2}
    1 = 2 (inequality doesnt hold)

    f{3} = 3* f{3}
    1= 3 {inequality doesnt hold)

    the inequality holds IFF f(x) = 0. but,
    f(1) = 1 . f{1}
    so , f{1} can / cannot be 0. but we cant say for sure.

    (have Pmed u the source of the question)
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