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#1 2010-08-04 15:49:22
- Mirage1
- Guest
Algerba and Surds! Help!
Find the exact value of
x² + 1/x²
if x = 1 + 2 * square root of 3 / 1 - 2 * square root of 3
Answer: 434/121 = 3 71/121
Does anyone know how to arrive at this answer?? Help much appreciated
#2 2010-08-04 16:30:36
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Algerba and Surds! Help!
Hi Mirage1;
Mirage1 wrote:
if x = 1 + 2 * square root of 3 / 1 - 2 * square root of 3
I guess you mean:
You can use the identity:
To make the coming multiplications easier say,
Remember that:
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 2010-08-05 05:27:43
- soroban
- Member
- Registered: 2007-03-09
- Posts: 452
Re: Algerba and Surds! Help!
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