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

1 Answer
Jan 14, 2018

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]}