Would anyone like to explain to me how I would go about finding the domain and range of an exponential/logarithmic function?

Question

anonymous · Answer

For example: f(x) = log(x + 1). Find the domain. I just need a little review!

eyust707 · Answer

heres my trick

eyust707 · Answer

"Domain, Range"
    x       ,    y

eyust707 · Answer

Domain is "all possible x values"

eyust707 · Answer

Range is all possible y values

eyust707 · Answer

Assuming it is a base 10 log...
Thats the same as saying
$10^{y} = x + 1$

eyust707 · Answer

Domain would be what possible x's can you put in there and still have real numbers?

eyust707 · Answer

the smallest an exponent can get is 0....

eyust707 · Answer

This means that x must be greater than -1

eyust707 · Answer

And we also notice that exponentials can get really big... so x in this case could get as big as you want... x would have to be less than or equal to $ \infty$

eyust707 · Answer

$$-1 \le x \le \infty$$

anonymous · Answer

@eyust707 simple way to put it! Thanks for the awesome explanation. Can you tell me anything about the purpose of asymptotes and how I would be able to find that as well?

eyust707 · Answer

sure first lets look at the graph

eyust707 · Answer

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