The sum of the cubes of three consecutive natural numbers is divisible by
The sum of the cubes of three consecutive natural numbers is divisible by
26
25
9
7
Solution
Let the three consecutive natural numbers \((n-1), n, n+1\) where \(n \geq 2\)
\(\therefore\) Sum of cubes of the three consecutive natural numbers is
\((n-1)^3+n^3+(n+1)^3=3 n^3+6 n=3 n\left(n^2+2\right)\)
For each value of \(n \geq 2\), the expression \(3 n\left(n^2+2\right)\) is divisible by 9 . Hence, option (c) is correct.