(x^2-5xy)(-3xy) (2x^3-3x^2+x+30):(x+2) (x+3)^2+(7-x)^2+2(x+3)(7-x) giùm mình đi nha các bạn 03/12/2021 Bởi Sadie (x^2-5xy)(-3xy) (2x^3-3x^2+x+30):(x+2) (x+3)^2+(7-x)^2+2(x+3)(7-x) giùm mình đi nha các bạn
`(x^2-5xy)(-3xy)` `=x^2.(-3xy)-5xy.(-3xy)` `=-3x^3 y+15x^2 y^2` `(2x^3-3x^2+x+30):(x+2)` `=(2x^3+4x^2-7x^2-14x+15x+30):(x+2)` `=[2x^2(x+2)-7x(x+2)+15(x+2)]:(x+2)` `=(x+2)(2x^2-7x+15):(x+2)` `=2x^2-7x+15` `(x+3)^2+(7-x)^2+2(x+3)(7-x)` `=(x+3+7-x)^2` `=10^2` `=100` Bình luận
`(x^2-5xy)(-3xy)`
`=x^2.(-3xy)-5xy.(-3xy)`
`=-3x^3 y+15x^2 y^2`
`(2x^3-3x^2+x+30):(x+2)`
`=(2x^3+4x^2-7x^2-14x+15x+30):(x+2)`
`=[2x^2(x+2)-7x(x+2)+15(x+2)]:(x+2)`
`=(x+2)(2x^2-7x+15):(x+2)`
`=2x^2-7x+15`
`(x+3)^2+(7-x)^2+2(x+3)(7-x)`
`=(x+3+7-x)^2`
`=10^2`
`=100`
Bạn tham khảo