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#1 2017-10-03 18:34:24

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

A simple question is not being able to solve by me

Last edited by iamaditya (2017-10-04 18:30:28)


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 2017-10-03 21:10:24

bob bundy
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Registered: 2010-06-20
Posts: 8,137

Re: A simple question is not being able to solve by me

I'm wondering what happens if you just expand the brackets.  Bit buzy right now.  I'll have a look later.

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 2017-10-03 22:51:55

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

Re: A simple question is not being able to solve by me

I'm sorry I gave the question wrong, I edited it . Now see.


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 2017-10-03 22:58:04

bob bundy
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Registered: 2010-06-20
Posts: 8,137

Re: A simple question is not being able to solve by me

And is that xyz = 1 rather than abc = 1  ?

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 2017-10-03 23:24:32

bob bundy
Administrator
Registered: 2010-06-20
Posts: 8,137

Re: A simple question is not being able to solve by me

I've assumed that it's xyz = 1

Then I put everything over a common denominator, expanded all brackets and simplified.  The numerator and denominator came out the same so the expression = 1

It was a very complicated expansion, taking two sheets of A4, even with simplifications such as x.y^2.z = y so I won't post it here just yet.  I'll look for an easier way first.  Phew!

later edit: got it down to half a page of working but still the same method.

Bob

Last edited by bob bundy (2017-10-04 01:00:17)


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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#6 2017-10-04 18:31:35

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

Re: A simple question is not being able to solve by me

bob bundy wrote:

And is that xyz = 1 rather than abc = 1  ?

Bob

Yeah it is.

I solved it but it took 2 whole pages to solve it. Phew! I finally got the numerator and denominator as equal and hence it is equal to 1.


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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#7 2017-10-04 18:45:29

bob bundy
Administrator
Registered: 2010-06-20
Posts: 8,137

Re: A simple question is not being able to solve by me

Yes, me too.

I managed to shorten the proof by re-writing like this

and so on.

I feel as though there ought to be a 'slick' way to do this easily, but I haven't found it yet.

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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#8 2017-10-05 04:07:52

bob bundy
Administrator
Registered: 2010-06-20
Posts: 8,137

Re: A simple question is not being able to solve by me

I think you're going to love this:

multiply the first term top and bottom by y and the third by xy:

smile

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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