Question

Tính hợp lý: A = (5/3-3/7+9)-(2+5/7-2/3)+(8/7-4/3-10)

Answer 1

\(A=\left(\frac{5}{3}-\frac{3}{7}+9\right)-\left(2+\frac{5}{7}-\frac{2}{3}\right)+\left(\frac{8}{7}-\frac{4}{3}-10\right)\)

\(=\frac{5}{3}-\frac{3}{7}+9-2-\frac{5}{7}+\frac{2}{3}+\frac{8}{7}-\frac{4}{3}-10\)

\(=\left(\frac{5}{3}+\frac{2}{3}-\frac{4}{3}\right)-\left(\frac{3}{7}+\frac{5}{7}-\frac{8}{7}\right)+\left(9-2-10\right)\)

\(=1-0-3\)

\(=-2\)

Answer 2

5/3-3/7+9-2-5/7+2/3+8/7-4/3-10

(5/3-4/3+2/3)+(8/7-3/7-5/7)+(9-2-10)

1+0-3=-2