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#1 2016-11-27 19:05:48

Member
From: Planet Mars
Registered: 2016-11-15
Posts: 725

A series problem

(1/( √ 1+ √ 2))+(1/( √ 2+ √ 3))+(1/( √ 3+ √ 4))................(1/( √ 99+ √ 100))

Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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#2 2016-11-27 20:35:34

bob bundy
Registered: 2010-06-20
Posts: 8,139

Re: A series problem

Like this:

This is called rationalising the denominator.  Do this for every term and most bits cancel.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#3 2016-11-27 22:57:00

Member
From: Planet Mars
Registered: 2016-11-15
Posts: 725

Re: A series problem

Yeah then we would be getting

( √2- √1)( √3- √2)( √4- √3)........( √100- √99)

Then, how we will proceed next.

Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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#4 2016-11-27 23:17:22

bob bundy
Registered: 2010-06-20
Posts: 8,139

Re: A series problem

In post 1 the terms are added together.  So don't multiply those new terms; add them.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#5 2016-11-29 22:25:07

Member
From: Planet Mars
Registered: 2016-11-15
Posts: 725

Re: A series problem

Yeah, I'm extremely sorry. I don't know in which state of mind I was at that time that I did this big mistake. I was about to delete the message but I didn't get time. And thanks for your answer.

Practice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

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