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What is remainder
((4^17)+(17^4))/7 ??
Read Solution (Total 10)
-
- 1st let us consider 4^17/7
i.e ((4^3)^5 x 4^2)/7
4^3/7= 1(remainder) therefore now (1^5 x 4^2)/7 = (1 x 16)/7 = 2(remainder)
now consider (17^4)/7
i.e 17/7 = 3(remainder) therefore
(3^4)/7 = 81/7= 4(Remainder)
therefore total 2+4=6 rem(Ans)
- 10 years agoHelpfull: Yes(31) No(6)
- 4^17=unit digit 4,
17^4 unit digit=1
so 1+4=5
5/7 gives 5 as remainder
ans=5
- 10 years agoHelpfull: Yes(9) No(4)
- 4^17=unit digit 4,
17^4 unit digit=7
so 7+4=11
11/7 gives 4 as remainder
ans=4 - 10 years agoHelpfull: Yes(6) No(12)
- 4^17 mod 7= (7-3)^17 mod 7= (-3)^17 mod 7 {since, 7^17 mod 7=0}
but -3^3 mod 7= -27 mod 7= 1 => -3^17= (-3^3)^5 mod 7 x -3^2 mod 7= 1x5= 5
also
17^4 mod 7= (7*2+3)^4 mod 7= 3^4 mod 7 {{since, (2*7)^4 mod 7=0}}
=81 mod 7= 4
Hence (5+4) mod 7= 2 (Ans) - 10 years agoHelpfull: Yes(5) No(3)
- ans is 0.
- 10 years agoHelpfull: Yes(3) No(7)
- 5
4^17+17^4
REM 4+ REM 1
5/7
=5 - 10 years agoHelpfull: Yes(1) No(1)
- (4^17+17^4)/7
=(2^34+(14+3)^4)/7
=((2^3)^31)/7+((14+3)^4)/7
=(8^31)/7+(3^4)/7 [as 14 or its multiples are always divisible by 7]
=((7+1)^31)/7+(27/7)+(3/7)
=1/7 (remainder) + (28-1)/7 + 3/7
=1/7 +(-1/7) (remainder) +3/7
=3/7
so the remainder is 3 - 10 years agoHelpfull: Yes(1) No(2)
- ((4^3)^5 .4^2)/7
since 64/7 gives 1
thus 1*4^2/7=16/7 gives 2 as remainder .........1
17/4 gives 3 as rem
so 3*3*3*3/7 gives 1 remainder from (27/7) and 3 from 3/7 so 3 as the remainder ......2
from 1 and 2 we have 6 as the remainder - 10 years agoHelpfull: Yes(0) No(0)
- because (2^10)^odd=24 than from question 4^17= 2^17+2 =2^19 =24
and 17^4=83521 now add both number 24+83521=83545 divide by 7 which is equal to 11935 and remainder should be 0. - 10 years agoHelpfull: Yes(0) No(1)
- 4 power odd num is 4...7 power 4 is 1(unit digit)...4+1=5...5/7...remainder is 2
- 10 years agoHelpfull: Yes(0) No(0)
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