Đáp án+Giải thích các bước giải:
`g)[7(a-b)^5-5(a-b)^3]:(b-a)^2`
`=[7(a-b)^5-5(a-b)^3]:(a-b)^2`
`=7(a-b)^5:(a-b)^2-5(a-b)^3:(a-b)^2`
`=7(a-b)^3-5(a-b)`
`=7(a^3-3a^2b+3ab^2-b^3)-5a+5b`
`=7a^3-21a^2b+21ab^2-7b^3-5a+5b`
`=7a^3-7b^3-21a^2b+21ab^2-5a+5b`
`.........................`
`h)[7(a-3b)^3+(a-3b)]:(2a-6b)`
`=[7(a-3b)^3+(a-3b)]:[2(a-3b)]`
`={2(a-3b)[7/2(a-3b)^2+1/2]}:[2(a-3b)]`
`=7/2(a-3b)^2+1/2`
`=7/2(a^2-6ab+9b^2)+1/2`
`=7/2a^2-21ab+63/2b^2+1/2`
`.................................`
`k)(x^3+3x^2y+3xy^2+y^3):(2x+2y)`
`=(x+y)^3:[2(x+y)]`
`=1/2(x+y)^2`
`=1/2(x^2+2xy+y^2)`
`=1/2x^2+xy+1/2y^2`
`.....................................`
-Chúc bạn học tốt!!!-
`#Rùa~ ~ ~`
