What is the domain and range of #f(x) = ln (10-x)#?

1 Answer
Jan 14, 2018

Answer:

domain: #x<10#
range: #RR#

Explanation:

#ln(x)# graph: graph{ln(x) [-10, 10, -5, 5]}
the natural log function only outputs a real number if the input is greater than 0.

this means the domain is #10-x>0#
#x<10#

the natural log function can output any real number, so the range is all real numbers.

check with this graph
#f(x)=ln(10-x)# graph{ln(10-x) [-10, 10, -5, 5]}