On diving, we get` (1 - x^8)/(1 - x^4) ` `= 65/64` `or ((1 - x^4) (1 + x^4))/((1 - x^4))` `= 65/64 or 1 + x^4` `= 65/64` `:. x^4 = (65/64 - 1)` `= 1/64 or x = (1/2^6)^(1/4)` `= + 1/(2^(3/2))` - `= + 1/(2sqrt(2))` -