## jmallis 3 years ago The graph of the function has more than one turning point. Use the graphing calculator to find the coordinates of the turning point that lies in the given interval. f(x)= 7x^3 -9x^2 -x+1, [-1, 10] The coordinates of the turning point are

1. TuringTest

Is this calculus?

2. jmallis

College Algebra

3. sauravshakya

Find f'(x)

4. TuringTest

The asker said algebra, so presumably that means no calculus allowed.

5. jmallis

So what do I do?

6. TuringTest

it would certainly be a much easier calculus problem not sure I know a method for this using only algebra, I'll have to think on it...

7. jmallis

ok

8. sauravshakya

Graph it

9. TuringTest

that's all I can think of too

10. jmallis

And the calculus way?

11. TuringTest

find x=a such that f'(a)=0

12. TuringTest

...in the given interval

13. cinar
14. jmallis

ok so what would the coordinates of the turning point?

15. cinar

It says "Use the graphing calculator to find the coordinates of the turning point that lies in the given interval"

16. TuringTest

wow I managed to not even read the post :P thanks cinar

17. jmallis

I dont have one

18. cinar

(:

19. TuringTest

the website wolfram alpha is a pretty good one http://www.wolframalpha.com/

20. TuringTest

that site serves as a graphing calculator

21. jmallis

laptop blocked it

22. cinar
23. TuringTest

that method again requires calculus your three options are to buy the graphing calculator, get wolfram working on your laptop, or learn calculus besides that I have no ideas

24. cinar

I guess you have to use derivative

25. cinar

they are roughly (0.9,-2) (0.1,1) but exactly

26. jmallis

It was (-0.05, 1.03)

27. cinar
28. TuringTest

wolfram disagrees o_O

29. cinar
30. cinar

that's right, I just used my eyes (:

31. cinar