Lê Quốc Trần Anh Coordinator
01/08/2017 at 09:04-
Condition : \(a,b,c,d\in N;a,b,c,d< 10;a\ne0\)
\(\left[b,c,d\right]\ge0\Rightarrow a^a\le100\Rightarrow a\in\left\{1;2;3\right\}\)
If a = 1,then \(\left[b,c,d\right]=100-1^1=99=3^2.11\)
So,there'll be at least 1 number that have the factor 11 in its/their form of prime factorization (asburd since b,c,d < 10)
If a = 2,then \(\left[b,c,d\right]=100-2^2=96=2^5.3\)
So,there'll be at least 1 number that have the factor 25 in its/their form of prime factorization (asburd)
If a = 3,then \(\left[b,c,d\right]=100-3^3=73\)
So,there'll be at least 1 number that have the factor 73 in its/their form of prime factorization (asburd)
Hence,there's no satisfied number
Lê Quốc Trần Anh selected this answer. -
Dao Trong Luan 01/08/2017 at 20:02
We have a,b,c,d are four digits so \(0\le a,b,c,d\le9\)
Because aa + [b,c,d] = 100
=> aa \(\le100\)=> a \(\in\left\{1,2,3\right\}\)
If a = 1
=> [b,c,d] = 100 - 1 = 99 = 9.11
But 11 has two digits so b,c,d unsatisfactory
If a = 2
=> [b,c,d] = 100 - 22 = 96 = 3.32
But 32 has two digits so b,c,d unsatisfactory
If a = 3
=> [b,c,d] = 100 - 33 = 73
But 73 has two digits so b,c,d unsatisfactory
Therefore, there are no numbers satisfying the question