a) $\frac{-1}{4}$+ $\frac{3}{4}$
= $\frac{2}{4}$
= $\frac{1}{2}$
b)($-0,125^{3}$. $8^{3}$
= $(0,125.8)^{3}$
= $1^{3}$
= 1
c) 2$\frac{1}{2}$ + $\frac{4}{7}$: (- $\frac{8}{7}$ )
= $\frac{5}{2}$ + $\frac{4}{7}$ . $\frac{-7}{8}$
= $\frac{5}{2}$ + $\frac{4. (-7)}{7 . 8}$
= $\frac{5}{2}$ + $\frac{1.(- 1)}{1. 2}$
= $\frac{5}{2}$ + $\frac{-1}{2}$
= $\frac{4}{2}$
= 2.
d) ............................
= $\frac{1}{9}$. 3 - $\frac{2}{9}$ . $\frac{3}{2}$
= $\frac{1. 3}{9.1}$ - $\frac{2.3}{9.2}$
= $\frac{1.1}{3.1}$- $\frac{1.1}{3.1}$
= $\frac{1}{3}$ -$\frac{1}{3}$ = 0
Chúc bạn học tốt ~!!!!!!!!!!!!!!!!!!
