Question

Tính giá trị biểu thức:

\(\text{D}=\frac{\frac{4}{13}-\frac{4}{17}+\frac{12}{23}}{\frac{6}{13}-\frac{6}{17}+\frac{18}{23}}\)

Answer 1

Xét : 6/13 - 6/17 + 18/23

= 4/13 . 3/2 - 4/17 . 3/2 + 12/23 . 3/2

= 3/2.(4/13-4/17+12/23)

=> D = 1/(3/2) = 2/3

Tk mk nha

Answer 2

\(D=\frac{\frac{4}{13}-\frac{4}{17}+\frac{12}{23}}{\frac{6}{13}-\frac{6}{17}+\frac{18}{23}}=\frac{4}{6}-\frac{4}{6}+\frac{12}{18}=\frac{2}{3}\)