Question

The position of an object at time t is given by s(t) = -4 - 2t. Find the instantaneous velocity at t = 6 by finding the derivative.

Answer 1

@Coolsector

Answer 2

This is what i have done so far but i do not feel that is correct because i haven't used "t=6"

-2(x+h)-4-(-4-2x)/h
-2x-2h-4+4+2x/h
-2h/h
-2

Answer 3

@terenzreignz can you help? :o

Answer 4

Differentiate?

Answer 5

I'm not sure what that means :o

Answer 6

You get the derivative...

Answer 7

With respect to t.
If you're given the position function with respect to time, then if you differentiate it, you get the velocity funciton.

Answer 8

function*

Answer 9

So is what i did not how you find the derivative?

Answer 10

Oh, lol, sorry. Yes, you got the derivative -2, which is correct...

Answer 11

Haha okay so do i need to do anything with that or is that my final answer?

Answer 12

Well, you said you're worrying about why you haven't used the fact that t = 6, right?

Answer 13

Yea:P i was confused why it was there since i didn't use it when i thought i had solved it

Answer 14

You differentiated, and you got a constant... it only means that the derivative (velocity) does not depend on the time, ergo, it's constant, or the same, all throughout.

:)

Answer 15

Alright :D thanks again ^.^