Factorization

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Factorization

by C » Fri Feb 19, 2010 6:43 am
Hi guys,

I need some help with basic quant:

What is the easiest way to factorize?

How do I proceed to factorize 847?

Thanks.
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by vijay_venky » Fri Feb 19, 2010 6:53 am
The best way to factorize according to me is to start from the basic form

for example, the one that you have cited the basic form is 7x11^2

then write it in the form

(7^0+7^1)(11^0+11^1+11^2)

Take out a number from each of the groups and the result would be one of the factors.

example 7^2x11^1 is a factor.

Hope this helps.

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by shashank.ism » Fri Feb 19, 2010 7:01 am
C wrote:Hi guys,

I need some help with basic quant:

What is the easiest way to factorize?

How do I proceed to factorize 847?

Thanks.
see the easiest way to factorize is you have to keep in mind prime nos. in ur mind as much as possible atleast upto
40
now keep trying in mind which could divide the given no.
start from 2 if it is even
start from 3 if it is odd
start from 5 if last digit is 5 or 0 .
and continue
like here I start with 3(8+4+7=19 so No)
straight forward i will go for 7 yes
847 /7 = 121 =11x11
so 847 = 7x11x11......that is the appropriate approach..
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by C » Wed Feb 24, 2010 11:58 pm
Thanks, very helpful explanation!

Another challenge I have with factoring is problems like this:

x^3-3x^2+2x

or

n^2-14n+49

I can factor these given some intuitive thinking and try-fail-method, but it takes me to much time.

Does anyone have a good method for this kind of factoring?

Thank you!