F.2的factorization

我在題目中加上了括號令題目更易看清，希望我的理解沒錯。

(4m-1)2 / 15-5n × n2-32 / n-4mn ÷ (4m-1)

(4m - 1)2 / (15 - 5n) × (n2 - 32) / (n - 4mn) ÷ (4m - 1)

= [(4m - 1)2 / (5)(3 - n)] × [(n-3)(n+3) / (n)(1 - 4m)] × [1/(4m - 1)]
【Using a2-b2=(a-b)(a+b)】

= [(4m - 1)2 / (-5)(n - 3)] × [(n-3)(n+3) / (-n)(4m - 1)] × [1/(4m - 1)]

= (4m-1)2 (n-3) (n+3) / (-5)(n-3)(-n)(4m-1)2

= (n+3) / 5n