# Homework Help: Pre-cal help with probles like e^x, ln logs etc.

1. Dec 9, 2008

### austin1250

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. Dec 9, 2008

### Dick

You really figure out domains and ranges by getting experience with graphing functions. That's about it. For example, the range of 2^x is not (2,infinity). What is it? Try graphing it. For the log_10 question, log_a(x)=log_b(x)/log_b(a). You pick a and b appropriate to the problem.