# Thread: Urgent!! Parametric Equations!!

1. ## Urgent!! Parametric Equations!!

heyy.. i need to graph the following on my TI-83 plus in parametric mode.
y=2.5t^3-15t^2 and x= -1. i pretty much figured that one out, but i need to get the velocity, displacement, and acceleration equations and graph them. Thanks for ur help!! also, if its not too much trouble, a little description of wha it looks like would be great so i know i have the right graph

2. Originally Posted by samantha_malone
heyy.. i need to graph the following on my TI-83 plus in parametric mode.
y=2.5t^3-15t^2 and x= -1. i pretty much figured that one out, but i need to get the velocity, displacement, and acceleration equations and graph them. Thanks for ur help!! also, if its not too much trouble, a little description of wha it looks like would be great so i know i have the right graph
Are you sure this is right? If x is a constant, then the graph simply lies on a vertical line. (It has a max value, but stretches to negative infinity, or whatever y level you are using for the "ground.")

-Dan

yes i am sure it is right. the equation i gave u is supposed to simulate an elevator going up and down. i just need to find the velocity, acceleration and displacement

4. Originally Posted by samantha_malone
yes i am sure it is right. the equation i gave u is supposed to simulate an elevator going up and down. i just need to find the velocity, acceleration and displacement
Velocity in the y direction is $\frac{dy}{dt}$

and acceleration in the y direction is $\frac{d^2y}{dt^2}$

The elevator will have not velocity or acceleration in the x directions.

Remember that $\frac{d}{dt}t^n=(n)t^{n-1}$

Good luck.

5. am i going to be able to put this into my calculator??