Đáp án:
`(7/2012 + 7/9 - 1/4)/(5/9 - 3/2012 - 1/2)`
$\\$
`= ( (7/2012 + 7/9 - 1/4) × 2012 × 9 × 2)/( (5/9 - 3/2012 - 1/2) × 2012 × 9 × 2)`
$\\$
`= (7/2012 × 2012 × 9 × 2 + 7/9 × 2012 × 9 × 2 - 1/4 × 2012 × 9 × 2)/(5/9 × 2012 × 9 ×2 - 3/2012 × 2012 × 9 × 2 - 1/2 × 2012 × 9 × 2)`
$\\$
`= (7 × 9 × 2 + 7 × 2012 × 2 - 503 × 9 × 2)/(5 × 2012 × 2 - 3 × 9 × 2 - 1006 × 9 × 2)`
$\\$
`= (2 × (7 × 9 + 7 × 2012 - 503 × 9) )/(2 × (5 × 2012 - 3 × 9 - 1006 × 9) )`
$\\$
`= (7 × 9 + 7 × 2012 - 503 × 9)/(5 × 2012 - 3 × 9 - 1006 × 9)`
$\\$
`= (63 + 14084 - 4527)/(10060 - 27 - 9054)`
$\\$
`= (14147 - 4527)/(10033 - 9054)`
$\\$
`= 9620/979`
