How do you graph f(x)=4^(x-2) and state the domain and range?

1 Answer
Aug 31, 2017

domain is { x in RR }
range is { y in RR^+ : y != 0 }

Explanation:

f(x) = 4^(x-2) is a continuous function for all RR
So domain is { x in RR }

4^(x-2) can never equal 0.

If x >= 2 then 4^(x-2) >= 1

If x < 2 then 4^(x - 2) = 1/(4^(2 - x)

As x -> -oo then 1/(4^(2 - x)) -> 0

So range is { y in RR^+ : y != 0 }

y axis intercept is 1/16 where x = 0

The x axis is a horizontal asymptote.

graph{y = 4^(x - 2) [-8.89, 8.885, -4.444, 4.44]}