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What should be subtracted from 4^15 so that the remaining is divisible by 31
1. 0
2. 1
3. 2
4. 3
Read Solution (Total 10)
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- answer=1
4^15= 2^30=2^5^6=32^6=(31+1)^6
now (31+1)^6 / 31= 1^6 /31= 1(remainder)
so we have to sbtract 1 - 11 years agoHelpfull: Yes(52) No(0)
- 4^15=(4^3)^5=(64)^5=(62+2)^5=(2)^5=32
32-1=31
so one(1) should be subtracted - 11 years agoHelpfull: Yes(12) No(0)
- Using Remainder Theorem,
4^15/31
==> (4*4*4)^5/31
==> (2)^5/31
==> 32/31
Remainder is 1
Ans is :- 1 - 11 years agoHelpfull: Yes(5) No(2)
- 1
remainder theorm
((31 +1)^6)/31 = 1 - 11 years agoHelpfull: Yes(1) No(0)
- 4^15=4^3=64
if 64-2=62
62/2=31.
hence 2 is substracted. - 11 years agoHelpfull: Yes(1) No(1)
- we have to sbtract 1
- 11 years agoHelpfull: Yes(1) No(1)
- 4^15=2^30=(2^5)6=32^6/31=(31+1)^6/31
by applying binomial expansion=1^6=1 - 11 years agoHelpfull: Yes(1) No(0)
- answer = 1 only
- 11 years agoHelpfull: Yes(0) No(0)
- the remainder is 1
- 11 years agoHelpfull: Yes(0) No(0)
- what is the tricks for solving this kind of solution...kindly describe.....
- 11 years agoHelpfull: Yes(0) No(0)
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