The expression where , equals
(D) none of the foregoing expressions
What I have done
is a polynomial of degree 127. Now the highest degree of the polynomial in option (A), (B) and (C) is 127, 63 and 41 respectively. And therefore (A) is the correct answer.
I get to the correct answer but I don't think that my way of doing is correct. I mean what if, if option (B) was
Please show how should I approach to the problem to get to the correct answer without any confusion.