Analyzing x/t Graph - Accelerations & Inflections

[dazedy]

Homework Statement

Given this graph:
[PLAIN]http://img683.imageshack.us/img683/2403/xvtt.jpg

where is x>0, x<0, x=0, v>0, v<0, v=0, a>0, a<0, a=0?

The Attempt at a Solution

I figured out everything up to the accelerations, it's just been a long time since I've had to do a problem such as this.
Is the acceleration positive where the graph is concave up, negative where it is concave down, and 0 at the points of inflection?

 

[tiny-tim]

welcome to pf!

hi dazedy! welcome to pf!

Is the acceleration positive where the graph is concave up, negative where it is concave down, and 0 at the points of inflection?

Yup!

 

[dazedy]

Thanks :)
It's been years since I've had to look at a graph like this...