a.
b.
c.
d.
e.
f.
g.
1.
r = 2
r = 0.5
Not geometric
r = 0.8
r = w
r = √3
r = -3
2.
160, 320
1.25, 0.625
Not geometric
40.96, 32.768

w5, w6

9, 9√3
243, -729
3.
1024
0.5625
8192
47.59 (4s.f.)
0.00390625
1397.5
1048576z21
4.
2n
3n
q x 3n − 1
6 x (-1)n-1

5. r = 2, a = 0.5 and the sequence is 0.5, 1, 2 ,4, ... 0r r = -2, a = -0.5 and sequence is -0.5, 1, -2, 4,...

6.r = 1/3, a = 27 and the sequence is 27, 9, 3, 1, ...

7. 768 is the 8th term.

8. 4096 is the 7th term.

9. He would be doing 32, 768 press-ups and probably be very fit... or dead!

10. 4092

11. 6560

12. 27.95

13. 

14. 23.52

15. -682

16. 0

17. 739.93

18. 60

19. 10.67 ( to 4 sig. fig.)

20. 32

21. First term is 8

22. Common ratio is 2, first term is 2 and the sum of the 10th terms is 2046.

23. $10, 737, 418, 230

24. In six years time he will be 181 cm tall and his average height over the six years was 161 cm. (to 3 s.f.)

25. a. The differences between data values are not constant, but show a definite decrease with time:

b. The ratios between consecutive years are consistent with a constant ratio of 0.98, therefore it is a gemetric sequence.

c. L = 0.8(0.98)n-1

d. Total height = 18.68 m

e. Expected maximum = 40.5 metres