1no boss!! i substitued 0 n got ur ans...
then tried substitutin 1 n got 8...
but d ans is 2 :((
What is the remainder when
82n-(62)2n+1 is divided by 9
I got the answer as 7(just substituted )
Is it rite??
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14 Answers
1
1ya i got as 2
put n =0 .. hehe [1]
just hoped that it is really correct
62Theoretical solution
(9-1)2n-(63-1)2n+1 is divided by 9
Now can you solve..
9yes n=2
(63+1)n-(63-1)2n+1 = 63powers + 1 - (-1)2n+1=63β +2
1thats what happens when u substitute for 'n'...instead of doing that u cud have jus made (9-1)2n - (63-1)2n+1
to get the answer as 2...
it takes lesser tym to do this dan, to luk out for a comfortable 'n'...
1com'on u are kidding
n=0 is the best way over here
even idont like all these guessing in maths but at that time it was an advantage
1bt d thing is.......... if 7 is d answer then asnwer can also be 2.....
39total solutions
http://www.goiit.com/posts/show/995712/aakash_aieee_solutions_content-aieee-2009-solutions-and-analysis-929891.htm
1@mruna
l wat kind of n=0 are u putting to get answer as 7 please elaborate as i am utterly unable to understand ur method
11THE METHOD OF DIVISION IS NOT THE SAME FOR POSITIVE AND NEGATIVE NUMBERS
SO FOR n=0, U'LL GET -61/9
-63+2/9
-7 + 2/9
sO REMINDER IS 2!!!!
18\equiv -1(mod9)
so,
8^{2n}\equiv 1(mod9)
62\equiv -1(mod9)
so,
62^{2n+1}\equiv -1(mod9)
so,
8^{2n}-62^{2n+1}\equiv 2(mod9)
so, the answer is 2