Question

If 1+ x+ x²+ x³+.....x^n = (1 + x)(1 + x²)(1 + x^4)(1 + x^8)(1 + x^16) then n =
(a)32 (b)30 (c)16 (d)31

Answer 1

In Such case the ans is the addition of all the index. i.e.n=(1+2+4+8+16)=31. So the ans is (d)31.