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April 19th, 2017, 01:48 AM   #1
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Computing Average of Surds.

Can we compute average of Surds?
Example -

2√3,4√5,3√2,5√4,6√7,8√3,9√2

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Prashant S Akerkar
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April 19th, 2017, 01:51 AM   #2
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$Avg = \dfrac{2√3 + 4√5 + 3√2 + 5√4 + 6√7 + 8√3 + 9√2}{7}$
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April 19th, 2017, 05:15 AM   #3
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Surds are just numbers so of course we can calculate an average of them. Silly question.
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April 19th, 2017, 05:25 AM   #4
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It's not a silly question. It's about combining surds. You can add like surds but not unlike surds.
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April 19th, 2017, 08:13 AM   #5
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Quote:
Originally Posted by zylo View Post
You can add like surds but not unlike surds.
That is plain wrong.

$\sqrt{7} + \sqrt{7} = 2\sqrt{7}.$

Is that an exact answer?

$\sqrt{2} + \sqrt{5} = \sqrt{2} + \sqrt{5}.$

Then that too is an exact answer.

If you object that the second is not exact because it cannot be expressed exactly in decimals, then express the first exactly in decimals.

Silly questions invite even sillier responses.
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April 19th, 2017, 10:41 AM   #6
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prashantakerkar, I fear you are not being taken seriously. Do you have any idea why that might be?
Thanks from JeffM1
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April 19th, 2017, 10:53 AM   #7
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Thanks.

How we can further simplify to get the average of seven numbers which are Surds?

What's the answer for the above?

Thanks & Regards,
Prashant S Akerkar
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April 19th, 2017, 10:59 AM   #8
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Quote:
Originally Posted by prashantakerkar View Post
Thanks.

How we can further simplify to get the average of seven numbers which are Surds?

What's the answer for the above?

Thanks & Regards,
Prashant S Akerkar
Joppy already gave you the mathematically exact answer. If you want an approximate answer expressed in decimal notation, you must INDIVIDUALLY: approximate each surd to several more decimals than you care about, do the resulting arithmetic, and round the result to the number of decimal places you care about.

Do you understand that decimal notation cannot express exactly all real numbers?

Last edited by JeffM1; April 19th, 2017 at 11:02 AM.
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April 19th, 2017, 11:19 AM   #9
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Originally Posted by JeffM1 View Post
Do you understand that decimal notation cannot express exactly all real numbers?
No.
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April 19th, 2017, 12:09 PM   #10
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Quote:
Originally Posted by prashantakerkar View Post
Can we compute average of Surds?
...not to be confused with average length of Turds?
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