Help with series and sequence question (1 Viewer)

[dabatman]

Hi can anyone help me with this question, its from Maths in Focus 3 Units HSC.



Thanks in advance!

 

[pikachu975]

I'll just give hints:

a) Consider when a limiting sum exists in general - i.e. what values of the ratio are possible and what is the ratio?

b) Use the limiting sum formula and sub k in.

c) Use limiting sum formula and rearrange for k.

 

[dabatman]

ok thanks