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#1 2011-03-07 21:50:59

Alive
Member
Registered: 2010-08-14
Posts: 92

Help (Images provided)

These are 3 separate questions. How do you get the first few parts of the solution. i.e: 1/(1/a)-1... = 1/(1/a)-(a/a) = 1/(1-a)/a and the rest? What rules are there to learn to master these type of questions?

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All things can be forgiven if we can progress.
Yusuf Islam (formerly known as Cat Stevens)

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#2 2011-03-07 21:53:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Help (Images provided)

Hi Alive;

The first one is a little longer than it needs to be:

Times numerator and denominator by a.

The second one is the same:

Times top and bottom by a.

Can you now handle the 3rd one by using the same method?


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2011-03-07 22:26:56

Alive
Member
Registered: 2010-08-14
Posts: 92

Re: Help (Images provided)

For the third one...

4 - (1/x)
---------
1-2(1/x)

We times by x both..

4x - 1
-----
x - 2

Now we have to divide?? When do we know to divide or times..??
The rest is pretty straightforward.. But when do we know to divide or times..


All things can be forgiven if we can progress.
Yusuf Islam (formerly known as Cat Stevens)

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#4 2011-03-07 22:46:15

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Help (Images provided)

Hi;

You also have to know when you are done. The denominator does not go into the numerator evenly. It is sort of like 2 / 5. You can not do anything else so you are done.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#5 2011-03-07 22:58:28

Alive
Member
Registered: 2010-08-14
Posts: 92

Re: Help (Images provided)

Wait... the answer is the same..

4x - 1
------
x-2

No need of dividing anymore... I guess they did do it the long way, Thanks for the help!


All things can be forgiven if we can progress.
Yusuf Islam (formerly known as Cat Stevens)

Offline

#6 2011-03-07 22:59:54

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Help (Images provided)

Yes, I do not know why anyone would take the route they did. Talk about overkill.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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