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find remainder when (10^3+9^3)^1000 divided by 12^3
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-
- (10^3+9^3)^1000 / 12^3
= 1729^1000 / 1728
=> (1728*1+1)^1000 / 1728
=> 1^1000 / 1728
=> rem = 1 - 10 years agoHelpfull: Yes(100) No(4)
- Ans:1
10^3 UNIT DIGIT IS 0
9^3 UNIT DIGIT IS 9
(0+9)=9
(9)^1OOO=9^n unit digit is 1 9 1 9 1 9 1 9
so (9)^1OOO unit digit is=9
12^3 unit digit is =8
(10^3+9^3)^1000 divided by 12^3=9/8=remainder 1
- 10 years agoHelpfull: Yes(41) No(12)
- @sahitya
(1728*1+1)^1000/1728
(1728+1)
you take last digit in this term (1728+1)
so (1)^1000=1
1/1728=reminder is 1
using google calc
https://www.google.co.in/?gfe_rd=cr&ei=t1X7U4KlBavM8gftyoDoBQ&gws_rd=ssl#q=1+mod+1278
- 10 years agoHelpfull: Yes(5) No(0)
- 10^3+9^3 = 1729
12^3=1728
remainder will be 1^1000 = 1
- 10 years agoHelpfull: Yes(4) No(0)
- @vignesh
(10^3)=1000
(9^3)=729
1000+729=1729
we can write the 1729 in following from
(1728*1+1)^1000/1728
Take (+1)^1000 only
So (1)^1000=1
1/1728=reminder is 1 - 10 years agoHelpfull: Yes(3) No(0)
- =(1729)^1000/1728
=(1728+1)^1000/1728=1^1000/1728=1
- 10 years agoHelpfull: Yes(2) No(0)
- Unit digit of 10^3 is 0 while that of 9^3 is 9...hence unit digit of((10^3+9^3) is 9...
Now 9^1000gives a unit digit 1 .hence the remainder is 1 - 10 years agoHelpfull: Yes(1) No(0)
- 10^3+9^3=1729
1729^1000/1728 { 12^3=1728}
(1728+1)^1000/1728
1^1000/1728
1 is the req rem.Ans - 10 years agoHelpfull: Yes(1) No(0)
- 10^3+9^3=1729
12^3=1728
(1729)^1000/1728=(1728+1)^1000/1728
By remainders theroem:
rem=1 - 10 years agoHelpfull: Yes(1) No(0)
- it can be written as
(((10*10*10)/(12*12*12))+((9*9*9)/(12*12*12)))^1000
now
10/12=remainder is -2
9/12=remainder is -3
then,
we can write
((-2*-2*-2)+(-3*-3*-3))^1000
=(-35)^1000
which means 1^1000
so the remainder is 1 - 10 years agoHelpfull: Yes(1) No(0)
- (10^3+9^3)^1000=1729^1000
12^3=1728
when 1729%1728=1
1^1000=1
and 1%1728=1ans
=> (1728*1+1)^1000 / 1728
=> 1^1000 / 1728
=> rem = 1 - 10 years agoHelpfull: Yes(0) No(0)
- @rakesh: can u please explain the last two steps, i mean
1^1000/1728
rem=1 ??? how? - 10 years agoHelpfull: Yes(0) No(0)
- @ karthikeyan i have doubt in this step (1728*1+1)^1000/1728
(1728+1)
you take last digit in this term (1728+1)
so (1)^1000=1 - 10 years agoHelpfull: Yes(0) No(0)
- 1729^1000
For every 2 powers last digit will become 9
So 1729^1000 have 9 as remainder
For 12^3, last digit is 8
When 9 is divided by 8, the remainder is 1.
ANS: 1 - 10 years agoHelpfull: Yes(0) No(0)
- (10^3+9^3)^1000 / 12^3
= >{10^3+9^3)^10 / 12}^3
=> [ {1729}^10/12 ]^3
=> [ {1728 + 1}^10/12 ]^3
=> [ {1}^10/12 ]^ 3
=> 1 is the req rem. Ans.
- 10 years agoHelpfull: Yes(0) No(1)
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