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Equation integer part

what are all the steps to solve this equation?

97645643 6X * lower part( 97645643 / 6X)=X

thank you
Reply 1
Just to clarify to everyone, this is the expression:

976456436x976456436x=x97645643-6x \left\lfloor \dfrac{97645643}{6x}\right \rfloor = x
(edited 9 years ago)
If x is assumed to be an integer, you can move the 6x inside of the floor operation. This then cancels the 6x in the denominator. You are left with 97645643 - 97645643 = x
so x = 0

I'm not sure if this is a legitimate solution as this implies that 0 is in the denominator.
Reply 3
Original post by morgan8002
If x is assumed to be an integer, you can move the 6x inside of the floor operation. This then cancels the 6x in the denominator. You are left with 97645643 - 97645643 = x
so x = 0

I'm not sure if this is a legitimate solution as this implies that 0 is in the denominator.


This won't yield integer solutions for x.
Reply 4
thank you
976456436x976456436x=x97645643-6x \left\lfloor \dfrac{97645643}{6x}\right \rfloor = x

Rearranging..

Unparseable latex formula:

\dfrac{97645643}{x}\right \rfloor =1+6 \left\lfloor \dfrac{97645643}{6x}\right \rfloor



So x is a factor of 97645643.
Reply 6
but what are all the values of x, and how to calculate
Original post by gerva
but what are all the values of x, and how to calculate

As argued above, x is an integer which is 5 mod 6, which divides that long number. Sadly it's hard to factor that number.

Notice that babb \lfloor \dfrac{a}{b} \rfloor is "a rounded down to the nearest multiple of b". Hence ababa - b \lfloor \dfrac{a}{b} \rfloor is "the difference between a and the nearest multiple of b less than a": that is, it is a(modb)a \pmod b.

That is, we seek xx such that 97645643x(mod6x)97645643 \equiv x \pmod{6x}.

Does that help? (You may find the Chinese Remainder Theorem useful in seeing from another angle where this came from.)
(edited 9 years ago)
Reply 8
yes, thank you
Original post by gerva
yes, thank you

Does it? I can't really see that it does, but if it helped… :P Mind writing out your solution, because I still haven't solved it except by computer?
Original post by Smaug123
Does it? I can't really see that it does, but if it helped… :P Mind writing out your solution, because I still haven't solved it except by computer?


This one, by luck, comes out very quickly using Fermat's factorisation method.
Reply 11
is a help in more
Reply 12
if you want to see what I'm doing http://albericolepore.altervista.org/

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