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Ok I just need help understanding a little pre-cal

  1. Dec 9, 2008 #1
    In calc we are having like this flash card quiz and you have to apply things to the graph of like e^x or lnx.

    I was wondering how do you determine the domain range of graphs like these.

    for example e^x graph domain is all reals, and the range is 0 to infinity. How would you transform this graph and still determine the domain/range? would it be like 2^x and then the range just changes to 2 to infinity?

    And also question about ln verse log base of 10

    how would you go about like getting ln100 and find out what is that equal to of the follwing in base 10.

    ex answer choices are. log e , 2/log e , log(100e), log e /2 , none of these
  2. jcsd
  3. Dec 10, 2008 #2
    For an exponential a^x, the domain is all reals and range (0,infinity) for any constant a. The domain and range would change for linear transformations, as well as multiplicative inverses, so if you need to know about those, you should ask.

    You're second question has to do with the change of base formula.

    log_b (a) = log_k (a)/log_k (b) for any k that you want. You should be able to figure it out from there.
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