有幾條數學唔識做，邊個可以教我呀！＝．＝

1)　(4a-6b)^2
=(4a-6b)(4a-6b)+3a-2hb
=16a^2-48ab+36b^2+3a-2hb

2)5(a-b)^3-10(b-a)^2
=5(a^2-2ab+b^2)(a-b)-10(b^2-2ab+a^2)
=5(a^3-2a(^2)b+b^3-10b^2+20ab-10a^2
=5a^3-10a(^2)b+5b^3-10b^2+20ab-10a^2
=5a^3-10a^2+20ab-10a(^2)b-10b^2+5b^3

1)(4a-6b)^2+3a-2hb
多在個h....不能因式分解

2)5(a-b)^3-10(b-a)^2
= 5(a-b)^3-10(a-b)^2
= 5(a-b)^2 [(a-b)-2]
= 5(a-b)^2 (a-b-2)