Bài làm :
a, `[6.(- 1/3)^2 - 3 . (- 1/3) + 1] : ( - 1/3 - 1 )`
`= [6. 1/9 - (-1) + 1] : (- 4/3)`
`= [2/3 - (-1) + 1] : ( - 4/3)`
`= 8/3 : (- 4/3)`
`= -2`
b, `{(2/3)^3 . (- 3/4 )^2 . (-1)^(2003)}/{(2/5)^2 . (- 5/12)^3}`
`= {(2/3)^3 . (3/4 )^2 . (-1)}/{(2/5)^2 . (- 5/12)^3}`
`= {(2/3)^3 . (3/4 )^2}/{(2/5)^2 . (- 5/12)^3}`
`=` $\dfrac{\dfrac{2^3 . 3^2}{3^3 . 4^2}}{\dfrac{2^2 . 5^3}{5^2 . 12^3}}$
`= {2^3 . 3^2 . 5^2 . 12^3}/{3^3 . 4^2 . 2^2 . 5^3}`
`= {2^3 . 3^2 . 5^2 . 2^6 . 3^3}/{3^3 . 4^2 . 2^2 . 5^3}`
`= {2^9 . 3^5 . 5^2}/{3^3 . 2^6 . 5^3}`
`= {2^3 . 3^2}/{5}`
`= (72)/(5)`
