## Dodo1 Group Title curve problems? one year ago one year ago

1. Dodo1 Group Title

2. Luigi0210 Group Title

Do you know what the graph looks like?

3. Dodo1 Group Title

No, I have no idea!

4. Luigi0210 Group Title

Well it might be a good idea to sketch a graph

5. Dodo1 Group Title

would it possible to solve the problem　without a graph?

6. Dodo1 Group Title

would it be

7. Luigi0210 Group Title

Well yes but it be a bit harder since we don't know which graph is higher

8. Dodo1 Group Title

oh i see... how do you draw a graph

9. Luigi0210 Group Title

wait, are you finding total area or net area?

10. Dodo1 Group Title

it says find the area between the curves?

11. Luigi0210 Group Title

If I'm not mistaken then the graphs should look like this when graphed |dw:1366855841011:dw|

12. Dodo1 Group Title

sin and cos graph?

13. Luigi0210 Group Title

Uhm no, the ends of the graph go off into infinity after they have intersected

14. Dodo1 Group Title

Oh.

15. Luigi0210 Group Title

Now, do you notice anything about the two graphs?

16. Dodo1 Group Title

-they get smaller and smaller? -they intersects

17. Luigi0210 Group Title

Well yes but also they are reflections of one another

18. Dodo1 Group Title

Yes,

19. Luigi0210 Group Title

So that means that whatever area on graph has the other has the opposite area. Such as -x and x.

20. Dodo1 Group Title

Yes,

21. Luigi0210 Group Title

So that means the area would be zero

22. Dodo1 Group Title

the answer is zero?

23. Dodo1 Group Title

i thought i need more calculations

24. Luigi0210 Group Title

Well you could if you want but the answer would still be zero. These two graphs are going to cancel each others area out

25. Dodo1 Group Title

i entered zero into the answer but it tells me that it was wrong

26. Luigi0210 Group Title

Well let's solve it right now, do you know how to set it up as an integral?

27. Dodo1 Group Title

No, I have no idea!!

28. Dodo1 Group Title

@Luigi0210

29. Luigi0210 Group Title

Sorry I was trying to evaluate the problem

30. Luigi0210 Group Title

but anyways we would set up the problem like this: $\int\limits_{0}^{9} (x^3-14x^2+45x)-(-x^3+14x^2-45x) dx$

31. Zarkon Group Title

I'm betting that they want you to set up two different integrals...based on the two enclosed regions.

32. Dodo1 Group Title

so between...= minus. i got it

33. Luigi0210 Group Title

Setting up two equations would take a bit longer

34. Zarkon Group Title
35. Dodo1 Group Title

whats next step?

36. Luigi0210 Group Title

The answer I got was 253/2..

37. Luigi0210 Group Title

*243/2

38. Dodo1 Group Title

the answer was wrong but thanks for ur help!

39. Luigi0210 Group Title

I'm sorry I couldn't help you solve it..

40. Dodo1 Group Title

No thanks for your time!