Limits and Unknown Constants Question

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  1. bijesh12's Avatar
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    Limits and Unknown Constants Question
    I need help on the question 4 from the attachment... I've formed two simultaneous equations from information given.. How can i use the limit information, i can't say f(0)=2, as the function would be undefined..
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  2. nuodai's Avatar
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    Re: Limits and Unknown Constants Question
    (Original post by bijesh12)
    i can't say f(0)=2, as the function would be undefined..
    What makes you say that? Take the limit x \to 0 and see what you get. The fact that the limit has to be defined tells you something about one of the constants in particular, and the fact that it evaluates to 2 provides you with a third simultaneous equation. Then you have three simultaneous equations in three variables, so you just have to solve it and you're done.

    Edit: In fact taking the limit x \to 0 immediately gives you the value of two of the constants, using the fact that the limit exists (this gives you one of the constants) and is equal to 2 (this gives you the other). Then you just have two simultaneous equations in two variables to worry about.
    Last edited by nuodai; 14-05-2012 at 22:45.
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