n is an integer, r is redundant when (n-1)(n+1) is divided by 24. what is value of re
1,n is not divided by 2
2,n is not divided by 3
1,n is not divided by 2
2,n is not divided by 3
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Ok so assuming redundant was meant to be remainder and value of r is asked instead of ren is an integer, r is redundant when (n-1)(n+1) is divided by 24. what is value of re
1,n is not divided by 2
2,n is not divided by 3
24 = 3x8 so lets keep that in mind
1) n is not divisible by 2
That means (n-1) and (n+1) are both divisible by 2. Infact one of them would be divisible by 4. Thus (n-1)(n+1) will be divisible by 8. But we dont know if n will be divisible by 3 or not. If it is then r = 0 otherwise r is not equal to 0.
2) Similarly (n-1) or (n+2) is divisible by 3. However, we dont know if n is a prime number or an even number. To divide (n-1)(n+1) completely we need a 3 and an 8. This statement doesnt give us enough information
c) From 1) and 2) (n-1)(n+1) is divisible by 8 and 3. So r =0.
Answer should be C
---2) Similarly (n-1) or (n+2) is divisible by 3. However, we dont know if n is a prime number or an even number. To divide (n-1)(n+1) completely we need a 3 and an 8. This statement doesnt give us enough information ----
nevevares
pls, explain above thing.
nevevares
pls, explain above thing.
I think we should explain 2) as following
n is not divided by 3
so
n-1, or n+2 or n-2 or n+1 is divided by 3
that mean (n-1)(n+1) is divided by 3
from 1) we have (n-1)(n+1) is divided by 8
from 2), we have (n-1)(n+1) is divided by 3.
so both make it divided by 24, r=0
C is correct
n is not divided by 3
so
n-1, or n+2 or n-2 or n+1 is divided by 3
that mean (n-1)(n+1) is divided by 3
from 1) we have (n-1)(n+1) is divided by 8
from 2), we have (n-1)(n+1) is divided by 3.
so both make it divided by 24, r=0
C is correct
