Show that one and only one out of n, n+2 or n +4 is divisible by 3, where n is any
positive meger
Answers
Answer:
make me as a brainlist
Step-by-step explanation:
n+2 = 3q+2+2 =3q+4 = 3(q+1)+1 is not divisible by 3. n+4 = 3q+2+4 = 3q+6 = 3(q+2) is divisible by 3. thus one and only one out of n , n+2, n+4 is divisible by 3. hope this helps you.
Step-by-step explanation:
To solve this Question we must know the Euclids division Lemma or Division formula, both are the same thing but given different names that is
Dividend = Divisor × Quotient + Remainder
(This is always true let's check it through an example)
16 ÷ 3
_5__
3 | 16
-15
-----
1
16 = 3 × 5 + 1
But in division Lemma instead of writing the whole thing it is represented with alphabets
a = bq + r where 0 ≤ r < b (Think about it....) that is the remainders will be from 0 to number < b
where q is quotient and r is remainder, b is Divisor and a is dividend
1st case
a = n and b = 3 so r = 0, 1, 2
a = bq + r where 0 ≤ r < b
n = 3q + 0 = 3q
n = 3q + 1
n = 3q + 2
Here one and only 3q is where n is divisible by 3
2nd case
a = n + 2 and b = 3 so r = 0, 1, 2
a = bq + r where 0 ≤ r < b
n + 2 = 3q + 0 + 2 = 3q + 2
n + 2 = 3q + 1 + 2 = 3q + 3 = 3(q + 1)
n + 2 = 3q + 2 + 2 = 3q + 4
Here one and only 3(q + 1) is divisible by 3
3rd case
a = n + 4 and b = 3 so r = 0, 1, 2
a = bq + r where 0 ≤ r < b
n + 4 = 3q + 0 + 4 = 3q + 4
n + 4 = 3q + 1 + 4 = 3q + 5
n + 4 = 3q + 2 + 4 = 3q + 6 = 3(q + 2)
Here one and only 3(q + 2) is divisible by 3
Hence, if n is any positive integer, then one and only one out of n, n + 2 or n + 4 is divisible by 3
We can also check this
let's take n = 5
n = 5 is not divisible by 3
n + 2 = 7 is not divisible by 3
n + 4 = 9 is divisible by 3
so,if n is any positive integer, then one and only one out of n, n + 2 or n + 4 is divisible by 3
you can check this with any number
Hope you understood it........All the best