1. ## Airplane Problem

I'm looking for help on a logarithm graphing problem. When I graph the problem on my calculator, I get a nonsensical answer....the resulting graph looks like a tangent.
Here's the problem statement: "Climb Rate. The time t (in minutes) for a small plane to climb to an altitude of h feet is t=50log10 18,000/18,000-h."

The problem requires the following:
(a) determine the domain of the function appropriate for the context of the problem.
(b) use a graphing utility to graph the time function and identify any asymptotes
(c) as the plane approaches its absolute ceiling, what can be said about the time required to further increase its altitude?
(d) find the time for the plane to climb to an altitude of 4000 feet.

I'm sure the domain is 0 < h < 18,000. But my graph result is way off.
Would appreciate an explanation of how to graph this problem.
Thanks, Mike Clemmons

2. Originally Posted by Mike Clemmons
I'm looking for help on a logarithm graphing problem. When I graph the problem on my calculator, I get a nonsensical answer....the resulting graph looks like a tangent.
Here's the problem statement: "Climb Rate. The time t (in minutes) for a small plane to climb to an altitude of h feet is t=50log10 18,000/18,000-h."

The problem requires the following:
(a) determine the domain of the function appropriate for the context of the problem.
(b) use a graphing utility to graph the time function and identify any asymptotes
(c) as the plane approaches its absolute ceiling, what can be said about the time required to further increase its altitude?
(d) find the time for the plane to climb to an altitude of 4000 feet.

I'm sure the domain is 0 < h < 18,000. But my graph result is way off.
Would appreciate an explanation of how to graph this problem.
Thanks, Mike Clemmons
graph looks reasonable to me. the asymptote at h = 18000 (x = 18000) means the airplane can never reach that altitude.

tracing the graph shows that it takes about 5.46 minutes to reach an altitude of 4000 ft

screenshots from my TI-84 ...

3. ## Thanks for Help

Skeeter,
Thanks very much for this help. I must have missed a parentheses or something. I was convinced that I was using the same graphing formula....but kept getting a very non-answer.
Now I get the same answer. Again, thanks...much appreciated.
Mike Clemmons