If S is the sum of the series , by considering (1-x)S , or otherwise , prove that .
where x is not 1 .
Thanks a lot .
Hi
I am gonna give you general proof for this AGP, Arithmetico-Geomtric Series
is an AP and is a GP
The series we have is
Now
........(1)
..........(2)
We now substract (1) -(2)
.................................................. ...............................................
Now you should always remember the way of proof of this thing for any general term and apply as it is in your case
For going further , when -1< r <1
I have just given you a general proof to it.
What you should do-
- Don't just plug the values you won't be able to remember the formula for long
-Try to remember the way it was proved and find the value of sum, for your a,b,r & d every time you get this type of question
-If you do it this way , every question of A.G.P. will be solved