`***`Lời giải`***`
`(3/4x^3y^6+6/5x^4y^3-9/10x^5y):3/5x^3y`
`=((3x^3y^6)/4+(6x^4y^3)/5-(9x^5y)/10):3/5x^3y`
`=(15x^3y^6+24x^4y^3-18x^5y)/20:(3x^3y)/5`
`=(15x^3y^6+24x^4y^3-18x^5y)/20. 5/(3x^3y)`
`=(15x^3y^6+24x^4y^3-18x^5y)/(12x^3y)`
`=(12x^3y(5/4y^5+2xy^2-3/2x^2))/(12x^3y)`
`=5/4y^5+2xy^2-3/2x^2`