Question

Rút gọn:
a, \(\dfrac{4x^2-8xy}{10y-5x}\)
b, \(\dfrac{\left(x-2\right)^2-1}{x^2-6x+9}\)
c, \(\dfrac{x^2+8x+16}{x^2-16}\)

Answer 1

a, \(\dfrac{4x^2-8xy}{10y-5x}=\dfrac{4x\left(x-2y\right)}{5\left(2y-x\right)}=\dfrac{-4x}{5}\)

b, \(\dfrac{\left(x-2\right)^2-1}{x^2-6x+9}=\dfrac{\left(x-2-1\right)\left(x-2+1\right)}{\left(x-3\right)^2}\)

\(=\dfrac{\left(x-3\right)\left(x-1\right)}{\left(x-3\right)^2}=\dfrac{x-1}{x-3}\)

c, \(\dfrac{x^2+8x+16}{x^2-16}=\dfrac{\left(x+4\right)^2}{\left(x-4\right)\left(x+4\right)}=\dfrac{x+4}{x-4}\)