Question

    

Answer 1

em nên xoay ngang ảnh trước khi tải lên để theo dõi cho dễ nhé

Answer 2

a) $\dfrac{x^2-16}{4x - x^2} = \dfrac{(x-4)(x+4)}{x(4-x)} = \dfrac{-x-4}x$;

b) $\dfrac{x^2+4x+3}{2x + 6} = \dfrac{(x+1)(x+3)}{2(x+3)} = \dfrac{x+1}2$;

c) $\dfrac{15x(x+y)^3}{5y(x+y)^2} = \dfrac{3x(x+y)}{y}$;

d) $\dfrac{5(x-y)-3(y-x)}{10(x-y)} = \dfrac{8(x-y)}{10(x-y)} = \dfrac45$.