(1)a ^ 4 - 1
= (a ² + 1)(a ² - 1)
= (a ² + 1)(a + 1)(a - 1)
(2)P ² (a - 1)- P (a - 1)
= (P ² - P)(a - 1)
= P(P - 1)(a - 1)
(3)4 a ² (x ² - 4 y ²)
= 4 a ²(x + 2 y)(x - 2 y)
平方差公式:a ² - b ² = (a +b)(a - b)
(1)a ^ 4 - 1
= (a ² + 1)(a ² - 1)
= (a ² + 1)(a + 1)(a - 1)
(2)P ² (a - 1)- P (a - 1)
= (P ² - P)(a - 1)
= P(P - 1)(a - 1)
(3)4 a ² (x ² - 4 y ²)
= 4 a ²(x + 2 y)(x - 2 y)
平方差公式:a ² - b ² = (a +b)(a - b)