Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

**debjit625****Member**- Registered: 2012-07-23
- Posts: 101

Find the sum of the following geometric series

I got an answer of

But the book gives an answer of

I think its a mistake ,it should be

Or am I wrong

Just want to be sure...

Thanks

*Last edited by debjit625 (2013-03-10 21:26:58)*

Debjit Roy

___________________________________________________

The essence of mathematics lies in its freedom - Georg Cantor

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,772

Hi;

What happened to the n?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**debjit625****Member**- Registered: 2012-07-23
- Posts: 101

Ok I just got it

,my badSolved the problem

Debjit Roy

___________________________________________________

The essence of mathematics lies in its freedom - Georg Cantor

Offline

**debjit625****Member**- Registered: 2012-07-23
- Posts: 101

Sorry I was in hurry its will be -n .I edited it on the first post too...

Here is the answer

The problem was it just got out of my mind about multiplicative inverse i.e..

Thanks

*Last edited by debjit625 (2013-03-10 21:27:53)*

Debjit Roy

___________________________________________________

The essence of mathematics lies in its freedom - Georg Cantor

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,772

That is okay. Glad you figured it out.

That is the answer mathematica gets too.

*Last edited by bobbym (2013-03-10 21:32:44)*

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

Pages: **1**