Question

tính thuận tiện nhất?

\(\left(1-\dfrac{1}{2}\right):\left(1-\dfrac{1}{3}\right):\left(1-\dfrac{1}{4}\right)\)

Answer 1

\(=\left(\dfrac{1}{2}\right):\left(\dfrac{2}{3}\right):\left(\dfrac{3}{4}\right)=\dfrac{1}{2}x\dfrac{3}{2}x\dfrac{4}{3}=\dfrac{1x3x4}{2x2x3}=\dfrac{12}{12}=1\)

Answer 2

=\(\dfrac{1}{2}:\dfrac{2}{3}:\dfrac{3}{4}=\dfrac{1}{2}x\dfrac{3}{2}x\dfrac{4}{3}=\dfrac{1x3x4}{2x2x3}=\dfrac{1x3x2x2}{2x2x3}=\dfrac{1}{1}=1\)

đây là làm như thường chứ cũng chả phải thuận tiện

Answer 3

`(1-1/2) : ( 1-1/3) : ( 1 - 1/4)`

` = 1/2 : 2/3 : 3/4`

` = 1/2 xx 3/2 xx 4/3`

` = (1xx3xx4)/(2xx2xx3)`

` = 12/12`

` = 1`