# Thread: is this an increasing or decreasing function?

1. ## is this an increasing or decreasing function?

V(t)= 25(0.85)^t

2. ## Re: is this an increasing or decreasing function?

What is the derivative? This will tell you where it is increasing and/or decreasing, whether it is monotonic, etc.

Hint: to differentiate, take the natural log of both sides first, then implicitly differentiate.

4. ## Re: is this an increasing or decreasing function?

I was trying to engage the OP to do this on their own, as presumably they have already seen exponential functions differentiated in lecture and in their textbook.

We try not to come right behind someone who has posted a hint and give a full solution, especially when there has been no work shown by the OP.

5. ## Re: is this an increasing or decreasing function?

okay. noted. although sometimes people need to be walked through things. not everyone who is looking for an answer on the internet is trying to avoid doing real work.

but I will respect the forum standards in the future

6. ## Re: is this an increasing or decreasing function?

Nice video, by the way!

I see that you have recently registered, so you didn't know, and I appreciate your maturity.

Every forum is different, and on this one the standard is for the OP to show some effort, some thoughts, or to at least say, I have no clue how to do this, etc.

Decreasing