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what is the remainder of (32^31^301) when it is divided by 9?
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- ans:5
solve by using remainder theorem.
- 9 years agoHelpfull: Yes(27) No(5)
- 32^31^301
when 31 divided by 9 gives remainder 5
5 5^2 5^3 all gives the same unit digit 5
so 31^32 gives unit digit 5
same rule applicable to 31^301
when 31 divided by 9 gives remainder 4
4 4^2 4^3 4^4 =4 6 4 6 unit place repeats for every 2 times i,e for even power its uint place is 6 and for odd its 4
as 301 is odd its unit place is 4
so 31^32^301=31^4=5^4=5 is the ans
- 9 years agoHelpfull: Yes(12) No(31)
- 32^31^301 /9=?
STEP 1: 32/9= REMAINDER =5;
STEP 2: 31^301/9; TAKE UNIT DIGIT'S CYCLE. THEREFORE NUM OF CYCLES =1, THUS 1/9;
STEP 3: 5^1/9= 5/9;
STEP 4: IF THE NUMERATOR IS LESS THAN DEMONINATOR THEN NUMERATOR IS THE ANSWER. ANS->5 - 7 years agoHelpfull: Yes(9) No(0)
- 32^31^301/9
first step 32/9 the rem is 5
second step 5^31^301/9
take the unit digit : 31^301/9
cyclicity of 1 is 1
301/1 have rem =0 3^0 =1
5^1/9=5/9
ans 5
- 9 years agoHelpfull: Yes(4) No(3)
- SOLVING BY REMAINDER THEOREM
32 wen divided by 9 gives 5 as remainder
now 5^31^301
now 31 divided by 9 gives 4 as remainder
now 5^4^301
4^301 shall give unit place as 4
so now 5^4=20
20/9=2 as remainder so 2 is rt
- 9 years agoHelpfull: Yes(3) No(29)
- 34/9 gives remainder 7
(7^3)/9 gives remainder 1
(((7^3)^3110)/9*7/9) = 1*7 = 7 - 9 years agoHelpfull: Yes(2) No(31)
- 301=4n+1
31=4n+3
so 32^3^1/9=5^3/9=8 as rem - 9 years agoHelpfull: Yes(2) No(9)
- Use concept of negative remainder
= 32^31^301/9
= 32^9331/9
= (-4)^9331/9 --------32/9 will give -4
= ([(-4)^3]^3110 * (-4))/9
= ([-64]^3110 * (-4))/9 --------(-64)/9 will give (-1)
= ([-1]^3110 * (-4))/9
= 1*(-4)/9
= (-4)/9
= 5 - 9 years agoHelpfull: Yes(2) No(3)
- ans - 5
using a^(p-1)/p giver remainder 1
so (32^8)/9 giver remainder 1
unit digit of 31^301 is 1
so , 32^31^301=32^(8k+1)= 32^8k.32
(32^8k)/9 gives remainder 1
32 divide by 9 gives remainder 5
so 5.1=5
hence ans=5
- 8 years agoHelpfull: Yes(2) No(0)
- rem.=2
32^31^301=32^10k+1(since unit no. of 31^301=1)
=>(2^6)^8k(32*4)/9
=>128/9
rem.=2 - 9 years agoHelpfull: Yes(1) No(13)
- (32^31^301) mod 9 = (27 + 5)(31^301) mod 9 = 5(31^301) mod 9
Find out the last digit of 5n mod 9 till the sequence repeats.
51 mod 9 = 5
52 mod 9 = 7
53 mod 9 = 8
54 mod 9 = 4
55 mod 9 = 2
56 mod 9 = 1
As the sequence repeats after every 6 terms so express exponential term in the form of : (6x + N) and the question will reduce from 5(6x + N) mod 9 to 5N mod 9.
Therefore 31301 mod 6 = (30 + 1)301 = 1301 = 1
Therefore twe need to find : 51 mod 9 = 5
- 8 years agoHelpfull: Yes(1) No(0)
- (32^31^301)/9
(32^9331)/9
32 can be written as 2^5
so (2^5^9331)/9
(2^46655)/9
since the value of 2^3 is 8 which is closest to 9
it can be written as ((8^15551)(2^2))/9
so ((9-1)^15551)/9 can be written as ((-1)^15551)/9
finally , (-1*4)/9
so -4/9,then the remainder is 5
Ans:5 - 7 years agoHelpfull: Yes(1) No(0)
- 32^31^301 = (32 raised to the power of 31) raised to the power 301.
now 32 = 2^5. so 32^31 = 2^(5*31) = 2^155
now we know that 2^3 = 8.
write down 2 ^155 = (2^3)^51 * 2^2 = 8^51 * 4
8/9 gives remainder 8 or -1. (-1)^51 = -1.
so now 32^31^301 is simplified to (-4)^301
now for odd power of 4 the unit digit is always 4.
so (-4)^301 = -4. when -4 is divided by 9 remainder is -4 or 9-4=5.
remainder can't be negative.
So 5 is the answer - 6 years agoHelpfull: Yes(1) No(0)
- (32^31)^301/9
=2^5^31^301/9
2^46655/9
=(2^3)^15551 *4/9
= rem 4 - 9 years agoHelpfull: Yes(0) No(2)
- Rem [34^31^301 / 9] = Rem [7^31^301 /9]
Now, we need to observe the pattern
7^1 when divided by 9, leaves a remainder of 7
7^2 when divided by 9, leaves a remainder of 4
7^3 when divided by 9, leaves a remainder of 1
And then the same cycle of 7, 4, and 1 will continue.
If a number is of the format of 7^(3k+1), it will leave a remainder of 7
If a number is of the format of 7^(3k+2), it will leave a remainder of 4
If a number is of the format of 7^(3k), it will leave a remainder of 1
The number given to us is 7^31^301
Let us find out Rem[Power / Cyclicity] t0 find out if it 7^(3k+1) or 7^(3k+2). We can just look at it and say that it is not 7^3k
Rem [31^301/3] = Rem [1^301/3] = 1
=> The number is of the format 7^(3k + 1)
=> Rem [7^31^301 /9] = 7 - 6 years agoHelpfull: Yes(0) No(1)
- 9=3^2
Euler number of 9=9*(1-1/3)=9*2/3=3*2=6
301=6*50+1 => Remainder=1 => 32^31^301 is reduced to 32^31^1
Similarly for 31, 31=6*5+1 => Remainder=1 => 32^31 is reduced to 32^1
Now, 32=9*3+5
Therefore remainder is 5 - 5 years agoHelpfull: Yes(0) No(0)
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