50đ Giúp e vs ạ e cảm ơn rất nhiều quy đồng mẫu thức nhiều phân thức

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Đáp án:

b) `(x+5)/(x^2+8x+16);x/(3x+12)` `(x ne -4)`

MTC: `3(x+4)^2`

T/c:

`(x+5)/(x^2+8x+16)=(x+5)/((x+4)^2)=(3(x+5))/(3(x+4)^2)=(3x+15)/(3(x+4)^2)`

`x/(3x+12)=x/(3(x+4))=(x(x+4))/(3(x+4)^2)=(x^2+4x)/(3(x+4)^2)`

c) `(6x^2)/(x^3-5x^2);(3x^2+15x)/(x^2-25)` `(x ne 0;x ne +-5)`

MTC : `x-5`

T/c:

`(6x^2)/(x^3-5x^2)=(6*x^2)/(x^2(x-5))=6/(x-5)`

`(3x^2+15x)/(x^2-25)=(3x(x+5))/((x-5)(x+5))=(3x)/(x-5)`

d) `1/(5x^3y^2);(x+1)/(15x^2y^4);(x-1)/(3xy^3)` `(x;y ne 0)`

MTC: `15x^3y^4`

T/c:

`1/(5x^3y^2)=(1*3y^2)/(5x^3y^2*3y^2)=(3y^2)/(15x^3y^4)`

`(x+1)/(15x^2y^4)=(x(x+1))/(15x^2y^4*x)=(x^2+x)/(15x^3y^4)`

`(x-1)/(3xy^3)=(5x^2y(x-1))/(5x^2y*3xy^3)=(5x^3y-5x^2y)/(15x^3y^4)`