Question

[nguyễn đức mạnh]

Tính bằng cách thuận tiện nhất:  

                          (1-1/2)* (1-1/3)* (1-1/4)

Answer 1

[Phạm Hoàng Phong]

\(\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times\left(1-\frac{1}{4}\right).\)

\(=\left(\frac{2}{2}-\frac{1}{2}\right)\times\left(\frac{3}{3}-\frac{1}{3}\right)\times\left(\frac{4}{4}-\frac{1}{4}\right)\)

\(=\frac{1}{2}\times\frac{2}{3}\times\frac{3}{4}\)

\(=\frac{1\times2\times3}{2\times3\times4}\)

\(=\frac{1}{4}\)

HT

Answer 2

[Nguyễn Huy Tú]

\(=\dfrac{\left(2-1\right)\left(3-1\right)\left(4-1\right)}{2.3.4}=\dfrac{1.2.3}{2.3.4}=\dfrac{1}{4}\)