How many times is polynomial-1 / 8x ^ 3-A ^ 2x ^ 2 + X? Is - A ^ 2 a coefficient or an unknown? How many times is 2 / 5x-by ^ 2?

How many times is polynomial-1 / 8x ^ 3-A ^ 2x ^ 2 + X? Is - A ^ 2 a coefficient or an unknown? How many times is 2 / 5x-by ^ 2?

In this case, we can't understand all the uninomial polynomials with the degree of - 2x A-2

F (x) = 1 / (1 + x) + 2 / (1 + x2) + 4 / (1 + x4) + 8 / (1 + x8) + 16 / (1 + x16) to find the value of F (2)
Wait for the answer!!!!!!!!!

This question is close to 1, the answer is 1, a little skill, but I forgot
How many times the power of X is twice the number of times of the previous term

Calculation: (x + 1 / x) (x2 + 1 / x2) (x4 + 1 / x4) (x8 + 1 / x8) (x2-1)
Thank you for your care. I will always remember
(≥} ≤) moved ～

(x+1/x)(x2+1/x2)(x4+1/x4)(x8+1/x8)(x2－1)=(x+1/x)(x2+1/x2)(x4+1/x4)(x8+1/x8)(x-1/x)(x)=(x2-1/x2)(x2+1/x2)(x4+1/x4)(x8+1/x8)(x)=(x4-1/x4)(x4+1/x4)(x8+1/x8)(x)=(x8-1/x8)(x)=x9-1/x7