\(=\dfrac{2a\left(a-b\right)}{a\left(c+d\right)-b\left(c+d\right)}=\dfrac{2a\left(a-b\right)}{\left(a-b\right)\left(c+d\right)}=\dfrac{2a}{c+d}\)

\(=\dfrac{\left(x+1\right)^2}{\left(x+1\right)\left(x^2-x+1\right)}=\dfrac{x+1}{x^2-x+1}\)

\(\frac{3x-6}{x-2}=\frac{3\left(x-2\right)}{x-2}=3\)

ĐKXĐ: \(x\ne2\)

\(\frac{3x-6}{x-2}\)

\(=\frac{3.\left(x-2\right)}{x-2}\)

\(=3\)

\(\frac{3x-6}{x-2}\)

\(=\frac{3\left(x-2\right)}{x-2}\)

\(=3\)

a.dkxd la x khac-1

b.rut gon ta duoc 1/x

c.gia tri 1/2014

= \(\frac{x^3.x-y^3.y}{y^3.x^3}\)= x.y

\(\frac{x^4-y^4}{y^3-x^3}=\frac{\left(x^2\right)^2-\left(y^2\right)^2}{\left(y-x\right)\left(y^2+xy+x^2\right)}=-\frac{\left(x^2-y^2\right)\left(x^2+y^2\right)}{\left(x-y\right)\left(x^2+xy+y^2\right)}=-\frac{\left(x-y\right)\left(x+y\right)\left(x^2+y^2\right)}{\left(x-y\right)\left(x^2+xy+y^2\right)}\)

\(=-\frac{\left(x+y\right)\left(x^2+y^2\right)}{x^2+xy+y^2}\)

\(\frac{a^3+1}{a^2+3a+4}=\frac{\left(a+1\right)\left(a^2-a+1\right)}{a^2+3a+4}=\left(a^2-a+1\right)\left(\frac{a+1}{a^2+3a+4}\right)\)