Answer To: I would like to get a quote on getting this assignment completed. If possible, I would also like...
Robert answered on Dec 23 2021
SECTION 6.1
Sol: (2)
Note that 12! 1 (1)(2 7)(3 9)(4 10) 5 8 6 11 12 1 1 1 1 1
1 1 1 1 0 mod13 .
Therefore 13 divides 12! + 1.
Sol: (4)
5
5
We can write 5! 25! as,
5! 25! 1 2 3 4 5 25!
30 29 28 27 26 25!
-1 30!
-1 -1
1 mod
31 , by Wilson's theorem,
So finally we can see that the remainder is 1.
Sol: (6)
First we find
7 8 9 15 16 17 23 24 25 43 7 8 9 4 5 6 1 2 3 10 10! 1 (mod 11).
So we can see that the remainder is 10.
Sol: (10)
10
200
2000 10 200
From Fermat's little theorem, we know that
6 1 (mod 11).
Then 6 6 1 1 mod 11
So we can see that the remainder is 1.
Sol: (14)
100
100
6
100
We aim to find the last digit of 3 in its base 7 expansion. Equivalently, we would
like to determine 3 mod 7.
By Fermat's little theorem
3 1 mod 7;
hence 3
6 14 4 4
100
= ( 3 ) ·3 3 81 4 mod 7.
So we can see that from the last step, the last digit of the base 7 expansion 3 is 4.
Sol: (22)
3
9 3
9 5 4 5
9 9
We have
0 mod3 ,
0 mod5 ,
Since and have the same parity, 0 mod 2 ,
By the
n n n n
n n n n n n n
n n n n
9
9
9
Chinese remainder theorem, since both and 0 are solutions to the
system 0 (mod 2), 0 (mod 3), and 0 (mod 5),
we have 0 (mod 2 3 5).
Therefore 30 divides .
n n
x x x
n n
n n
Sol: (42)
0 0
0
We have
0 0 ...
Since 0 mod
When 1 1.
p
p k p k p p p p
k
p
a b a b a b a b b a
k
p
p
k
k p
SECTION 7.1
Sol: (2) (a)
2 2 2 2100 2 5 2 5 4 2 25 5 40
Sol: (2) (b)
8 8 7256 2 2 2 128
Sol: (2) (c)
1001 7 11 13 7 11 13 7 1 11 1 13 1 7200
Sol: (2) (d)
2 3 5 7 11 13 2 3 5 7 11 13
2 1 3 1 5 1 7 1 11 1 13 1
1 2 4 6 10 12
5760
Sol: (2) (e)
8 4 2
8 7 4 3 2
10! 2 3 5 7
2 2 3 3 5 5 7 1
829440
Sol: (2) (f)
18 8 5 2
18 17 8 7 4 3 2
20! 2 3 5 7 11 13 17 19
2 2 3 3 5 5 7 7 11 1 13 1 17 1 19 1
416,084,687,585,280,000
Sol: (4) (a)
1 2
1 1
1 1
1 2
1 11
1 1
1 1
1 1
If 1, let 2 ... be the prime factorization of . If 0 then
2 ...
and
if 0 then ... .
If 1, then
r
r r
r r
a a ak
r
a a a ak
r r
a a a a
r r
n n p p p n k
n p p p p
k n p p p p
n
either 1; 1 2.n or k and n
Sol: (4) (b)
1 1
1 1 1 1
1
1 1
1
1 1 1 1
Using the notation developed in part (a),
If 2, then either 2 and 4; or 1 and - 2,
so 3 and 6; or 0 and - 2, so 3 and 3.
a a
a a a a
n k n k p p
p n k p p p n
Sol: (4) (c)
1 1 11 1
Using the notation developed in part (a),
If 3, then - 3,
which is impossible, so there are no solutions..
a a
n p p
Sol: (4) (d)
1Using the notation developed in part (a), if , then 1 = 4. Therefore,
no odd prime can appear in the factorization of to a power higher than 1. Further, 1
must be a divisor of 4, so
t tp n p p n
n p
p
k 1
must be one of 2; 3, or 5. Say 2 3 5 , where and are
0 or 1. Note that 2 2 which must divide 4, so is either 0, 1, 2, or 3. If 3,
then 0, and so one solution is 8. If 2,
k a b
k
n a b
k k
a b n k
2
k
then 2 = 2 which forces
1 and 0, so a second solution is 12. If 0 1, then 2 =1. This
forces 0 and 1. This gives us two more solutions 5 and 10.
Having exhausted all
a b n k or
a b n n
possibilities, we have the complete set of solutions: 5, 8, 10, and 12.
Sol: (8)
1 1 11 1 1
1 1 1 1
1 1 1
If 14, then 7 for some odd prime . Since the only factors of 14 are
2 and 7, either = 7 and 1 and hence 1 = 6 14 which is false, or 7 1,
but 1 is even, so 1 =14 or =
a a
n p p p
p a p p
p p p
15 which is not prime.
Therefore there are no solutions.
Sol: (12)
...