## anonymous one year ago ??

1. IrishBoy123

2. anonymous

?

3. IrishBoy123

do you have an approach?

4. anonymous

I think I have to derive this

5. zepdrix

$$\large\rm a(t)=s''(t)$$ Yes. And they want you to find $$\large\rm a(2)$$

6. zepdrix

$$\large\rm s'(t)=?$$

7. anonymous

It equals 3t^2/2√(t^3+1)

8. zepdrix

Good :)

9. zepdrix

Oo looks like you'll need quotient rule to achieve that second derivative, ya? :o

10. anonymous

Yesss and I got 3t(t^3+4)/4(t^3+1)^(3/2)

11. anonymous

So would I just plug 2 into that?

12. zepdrix

Hmm I got something very similar, but a (t^3+1)^(5/2) in the bottom. Lemme make sure I didn't make a boo boo somewhere.

13. zepdrix

Woops :) Ya I did. Looks like you are correct! Yes, proceed to plug in t=2.

14. anonymous

And then I got 2/3

15. zepdrix

yayyy good job \c:/

16. zepdrix

and the units are going to be ft/sec^2 in case you need that as well.

17. anonymous

Okay thank you so much!