Answer: a=x, then polynomial is zero.
a = x - 1/(x^2+x-1), then polynomial is one, but we have to note (x^2+x-1) != 0.
Step-by-step explanation:
The polynomial product is identically zero when a = x, since factor (x-a) becomes zero. Another way for a polynomial to not contain x is if it is a constant not zero. For example,
(x-a) = 1/(x^2+x-1)
a = x - 1/(x^2+x-1)
Substitute a = x - 1/(x^2+x-1) into
(x^2+x-1)(x-a) = (x^2+x-1)/(x^2+x-1) = 1.
