Answer:
The term
for (x²-4x+8) and for (x²+4x+8) is negative.
Explanation:
The x intercepts are the values of x in which the function is equal to zero. So if x⁴+64=(x²-4x+8)(x²+4x+8), the x intercepts are the values of x that satisfy:
(x²-4x+8) = 0 or (x²+4x+8) = 0
Then, the values of x that satisfy (ax²+bx+c) = 0 are calculated as:
or

So, if the term
is negative the graph of the function has no x-intercepts.
Then, for (x²-4x+8) = 0, we get:

At the same way, for (x²+4x+8) = 0, we get:
