Question

Rút gọn 

a) \(\frac{15x\left(x+y\right)^3}{5y\left(x+y\right)^2}\)

b) \(\frac{x^2+4x+3}{2x+6}\)

Answer 1

a) \(\frac{15x\left(x+y\right)^3}{5y\left(x+y\right)^2}\)

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

b) \(\frac{x^2+4x+3}{2x+6}\)

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

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

\(=\frac{\left(x+1\right)\left(x+3\right)}{2\left(x+3\right)}\)

\(=\frac{x+1}{2}\)

Answer 2

a) \(\frac{15x\left(x+y\right)^3}{5y\left(x+y\right)^2}=\frac{3x\left(x+y\right)}{y}=\frac{3x^2+3xy}{y}\)

b) \(\frac{x^2+4x+3}{2x+6}=\frac{x^2+3x+x+3}{2\left(x+3\right)}=\frac{x\left(x+3\right)+\left(x+3\right)}{2\left(x+3\right)}=\frac{\left(x+1\right)\left(x+3\right)}{2\left(x+3\right)}=\frac{x+1}{2}\)