[Maximum mark: 16]
Consider the arithmetic sequence
b,m,n,…
where b,m,n=0
|
|
(a) Show that 2m − n = b
Now consider the geometric sequence
b, r, u, …
where b, r, u ≠ 0 |
[2] |
(b) Show that r2 = bu
The first term of both sequences is b. It is given that n = u = 9 |
[1] |
(c) Show that m > 3
Consider the case where b = 25, r > 0 and n = u = 9 |
[2] |
(d.i) Write down the first four terms of the arithmetic sequence |
[2] |
(d.ii) Write down the first four terms of the geometric sequence
A new arithmetic sequence (vk)is formed by adding together corresponding terms of the two sequences:
vk = (term from arithmetic sequence) + ln (term from geometric sequence).
It is given that
v1 = 25 + ln 25, v2 = 17 + ln 15, |
[2] |
(e.i) Find the common difference of the sequence (vk) in terms of ln 3 and ln 5 |
[2] |
(e.ii) Show that
∑k=110vk=−110−25ln5+45ln3 |
[4] |