1 - 2.25x^8

Factor this

(1+3/2x^4) (1-3/2x^4) = (1+1.5x^4) (1-1.5x^4)

Step-by-step explanation:

2.25 = 9/4

putting decimals into fractions will make this easier

9/4 = 3/2 * 3/2

a²-b² = (a+b) (a-b)

1 - 2.25x^8 = 1² - (3/2x^4) ² = (1+3/2x^4) (1-3/2x^4) = (1+1.5x^4) (1-1.5x^4)