SOLUTION: Find the domain of g(x)=ln(x+4)? I am not sure what to do for this question with the ln? Help?

Algebra.Com
Question 147784: Find the domain of g(x)=ln(x+4)? I am not sure what to do for this question with the ln? Help?
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
note: ln is a logarithm where



Start with the given expression

Remember you cannot take the natural log of zero or of a negative value. So that means the argument must be greater than zero (i.e. the argument must be positive)

Set the inner expression greater than zero

Subtract 4 from both sides


Combine like terms on the right side


So that means x must be greater than in order for x to be in the domain

So the domain in set-builder notation is


So here is the domain in interval notation:


Notice if we graph , we get
notice how the graph never crosses the line . So this graphically verifies our answer.

and we can see that x must be greater than in order to lie on the graph

RELATED QUESTIONS

Find the inverse of the logarithmic function f(x)=-ln(x-2). Steps I've done so far:... (answered by robertb)
Hi Tutor, I am stuck on this problem. ln(x+2)-ln(4)=-ln x Do I take the ln of 2 and... (answered by nerdybill)
How do I find the domain of g(t)=log(t+2) and... (answered by Fombitz)
Hi, I have a multiple choice question and i'm stuck between the two answers. I have ln (answered by rapaljer)
ln(x + 4) + ln(x) = ln(x + 40) not sure what to... (answered by richard1234)
I am trying to find the domain for this problem... (answered by stanbon)
Solve: log base 4 (X) + Log base 8 (x) = 1 ln X/ln 4 + ln X/ln 8=1 2 ln X/2 ln 4 + ln... (answered by Fombitz)
I need helping solving this for x: (ln x)^3=ln x^4 Can I rewrite it as (ln x)^3=4lnx ? (answered by mathick)
Condense the expression to the logarithm of a single quanity... (answered by lwsshak3)