## anonymous one year ago I will medal/fan.. NO DIRECT ANSWERS Identify the type of sequence shown in the table below and select the appropriate response. n f(n) 1 540 2 500 3 460 4 420 5 380 Arithmetic sequence; common difference is −40 Arithmetic sequence; common difference is 40 Geometric sequence; common ratio is −40 Geometric sequence; common ratio is 40

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1. anonymous

@DanJS

2. DanJS

Do you know what each of those sequences look like?

3. anonymous

somewhat?! @DanJS

4. anonymous

yes.. okay! @DanJS @Hero

5. DanJS

Test if it follows each by using a couple of the points

6. anonymous

I am ust not good with the arithmatic stuff like what?

7. DanJS

If it increases the same amount for each increase in n, it is arithmetic

8. DanJS

or decreases

9. anonymous

so Its geometric, I am assuming?

10. DanJS

a geometric sequence will have the ratio of any two consecutive terms as a constant same value

11. DanJS
12. anonymous

so the answer is c or d, not a or b.

13. DanJS

looks like it is decreasing by 40 for every increase in n

14. DanJS

arithmetic, common difference in sucessive terms

15. anonymous

okay. so I mean a or b.. I was reading it wrong

16. anonymous

so the common difference is -40?

17. DanJS

yes, you see you are taking the previous term and adding (-40) to it every time

18. DanJS

an = a(n-1) - 40

19. anonymous

Can you help with another?

20. DanJS

If it were geometric, you can test out the ratio to see, by $\frac{ a _{n+1} }{ a _{n} } = r$

21. DanJS

the ratio will be a value for geometric, not the difference

22. anonymous

What is the exact value for the expression the square root of 56. − the square root of 14. + the square root of 126.? Simplify if possible. the square root of 14. 4 the square root of 14. 2 the square root of 42. 8 the square root of 42.

23. anonymous

sorry dinners ready... Maybe later, if ur on you could help? ::)

24. anonymous

@DanJS I think that the answer is B?