I should serve her until Sunday
X=a/b where b!=1, and a and b coprime.
Then multiply the equation through by b^(n-1). The first term is then not
an integer, and all the other terms are integers, and the sum is zeros, which
is impossible as the sum cannot be an integer.
Therefore if there is a rational solution it is integral.
Problem 2 is also easy.
The leading coeffienct is 1 and the last coefficent is 1. By the rational roots test a solution is either 1 or -1.
If the solution is 1 then:
But that cannot be.
If the solution is -1 then:
Which is it not.
Thus there are no solutions.