## anonymous 5 years ago calc ques

1. anonymous

cost of a cable is $6\sqrt{2}$. explain meaning of $\int\limits_{25}^{30}6\sqrt{x}$ in context of this problem

2. amistre64

it looks to be the length of the cable...maybe

3. anonymous

how did you get that? random guess?

4. amistre64

yeah...random guess :) gut feeling, intution.... sheer imagination

5. anonymous

i bleeve in ure answer since uve 211 fans :)

6. amistre64

ohnoyou dont, dont let this number fool ya...im an idiot in disguise :)

7. anonymous

hahaha

8. amistre64

without a complete problem to go on, thats just my guess :)

9. anonymous

well ok: company makes cables for 120 bucks a meter. for a fixed length, the price to make the cable is 6 rad 2.

10. amistre64

6sqrt(2) per foot?

11. anonymous

per meter but yes thats the right EQ

12. amistre64

er...meter

13. anonymous

:)

14. amistre64

then those numbers on top and beneath your integral sign would most likely be an interval of length of some sort...

15. anonymous

yes it is

16. amistre64

the "line" integral is a squareroot function... I know that much :)

17. anonymous

srry the 120 refers to the company SELLING price

18. anonymous

what is a line integral o.O

19. amistre64

the line integral is: $\int\limits_{} \sqrt{[f'(x)]^2+[g'(x)]^2} dx$

20. anonymous

uh ok

21. amistre64

or if y is a function of x...then f'(x) = 1 and you put in the functiuon for y on the other side

22. anonymous

o.o

23. amistre64

you might notice the format from finding the length of the hypotenuse of a right triangle

24. amistre64

c = sqrt(a^2 + b^2)

25. anonymous

yeah. missing the deriv's though

26. amistre64

yep, same concept, your trying to find the length of a curve by looking really close at it until it flattens out

27. anonymous

oh.

28. amistre64

then adding up all the little bitty flat parts

29. anonymous

so you still think the answer to my question is the total length of cable?

30. anonymous

doesnt seem right to me cause you alredady have 25 and 30. possibly something w/ the price?

31. amistre64

i think it has something to do with the length of a cable.... yeah, but to be sure id have to know the average rainfall in the amazon...you know the basics :)

32. amistre64

price involved with length....its in there someplce

33. anonymous

haha ok thx. i just gonna fake this one... thx for help!

34. amistre64

lol...sure thing ;)