Answer:
(x4+1)(x2-2)
Explanation:
x6-2x4+x2-2
separate them into two different expressions
(x6-2x4)+(x2-2)
factor out the common factor for each expression. For (x6-2x4), it would be x4, and for (x2-2), it would just be 1
x4(x2-2)+1(x2-2)
since there both expressions have the same factor, you can do a reverse of the distribution property and factor it like
(x4+1)(x2-2)