Question 38196
Some Rules that might help you

{{{a^n + b^n}}}
1.NEVER divisible by a-b
2.n is Odd   Divisible by a+b
  n is Even  NOT Divisible

{{{a^n - b^n}}}
1.ALWAYS divisible by a-b
2.n is Even   DIVISIBLE by a+b
  n is Odd  NOT Divisible by a+b