How do you find the domain, x intercept and vertical asymptotes of f(x)=lnx+2f(x)=lnx+2?

1 Answer
Feb 20, 2018

The lnxlnx-function only accepts positive values of xx

Explanation:

There is no upper limit to xx so the domain is:
0 < x < oo0<x<

As xx gets smaller the value of lnxlnx gets more and more negative, or in 'the language':

lim_(x->0) lnx=-oo

Meaning x=0 is the (only) vertical asymptote

The x-intercept is when lnx+2=0->lnx=-2
This means that x=e^(-2)~~0.135...

The range of the function is from -oo to +oo

graph{ln x+2 [-7.78, 8.026, -3.534, 4.37]}