Đáp án: + Giải thích các bước giải:
` a) (7.3^5 -3^4 +3^6 ):3^4`
`=7.3^5 : 3^4 - 3^4 :3^4 +3^6 :3^4`
`=7.3-1+3^2`
`=21-1+9`
`=29`
`b) (5x^4 -3x^3 +x^2 ):3x^2`
`=5x^4 :3x^2 -3x^3 :3x^2 +x^2 :3x^2`
`=5/3 x -x+1/3`
`c) (x^3 y^3 -1/2x^2 y^3 -x^3 y^2 ):1/3x^2 y^2`
`=x^3 y^3 :1/3x^2 y^2 -1/2x^2 y^3 :1/3x^2 y^2 -x^3 y^2 :1/3x^2 y^2 `
`=3xy -3/2 y -3x`
`d) [5(a-b)^3 +2(a-b)^2 ] :(a-b)^2`
`=(a-b)^2 [5(a-b)+2) :(a-b)^2`
`=5(a-b)+2`
`=5a-5b+2`
`e) (x^3 +8y^3 ):(x+2y)`
`=[x^3 +(2y)^3 ] :(x+2y)`
`=(x+2y)(x^2 -2xy+4y^2 ) :(x+2y)`
`=x^2 -2xy+4y^2`