Answer:
(x² - 9)(x² - 1)
Explanation:
Using Quadratic trinomials
Factor x⁴ - 10x² + 9
Step 1: Find the two integers whose product of 9 and whose sum of -10
Product
-9 × -1 = 9
Sum
-9 + -1 = -10
Step 2: Use -1 and -9 to complete the factors
x⁴ - 10x² + 9 = (x² - 9)(x² - 1)
Step 3: Use the foil method to check the factors
(x² - 9)(x² - 1) = x⁴ - 1x² - 9x² + 9 = x⁴ - 10x² + 9