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Homework Help: Continuous functions

  1. Sep 16, 2009 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
    If f and g are continuous functions with f(4)-5 and lim [5f(x) -g(x) ]=5 find g(4)
  2. jcsd
  3. Sep 16, 2009 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    Re: Continuity

    It's a bit tough to read what's going on here

    Is this supposed to be f(4)=5? the limit as x goes to 4 of [5f(x)-g(x)]=5? And you want to find g(4)?

    If so, you should be able to manipulate your limit equation using algebra of limit rules (for example, lim(a+b) = lim(a) + lim(b)). Then you need to know what happens to a continuous function when you have it inside of a limit. What do you think happens?
  4. Sep 17, 2009 #3


    Staff: Mentor

    Re: Continuity

    Aside from the confusion over whether you're saying that f(4) = -5 or f(4) = 5, do you want g(4) or [itex]\lim_{x \rightarrow 4} g(x)[/itex]?

    If you want to get help, you really need to concentrate on presenting your problem so that people can understand what you're asking. That would include spending some time on learning what the relevant symbols mean.
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