1. 5.4: Intervals of Direction

2. The formula gives the position of a particle at any given time.
warm-up
The formula gives the position of a particle at any given time.
Find the t-value where the particle comes to rest.

3. First let’s ask the question.
Today we will be finding when a particle or object changes direction given a formula.
First let’s ask the question.
When does an object change direction?
draw number lines to explain

4. Steps to finding when an object changes direction
1. set s’(t)=v(t)=0
2. make a number line to help you keep organized
3. check to the left and right of that value and make sure velocity changes direction
Exact same steps to see when the particle is moving to the left or right.

5. When does the particle change direction?
The formula below gives the velocity of a particle at any point. Find the x-values on this formula where the particle changes direction.
When does the particle change direction?
Give the intervals where the particle is traveling to the left.
Give the intervals where the particle is traveling to the right.