a)($\frac{3}{4}$-$\frac{5}{6}$)$^{2}$
=($\frac{18}{24}$-$\frac{20}{24}$)$^{2}$
=(-$\frac{1}{12}$)$^{2}$
=$\frac{1}{24}$
b)$\frac{5^{4} . 20^{4} }{25^{4} . 4^{5} }$
=$\frac{5^{4} . (4.5)^{4} }{(5^{2})^{4} . (2^{2})^{5} }$
=$\frac{5^{4} . 4^{4} . 5^{4} }{5^{10} . 2^{10} }$
=$\frac{5^{4} . 4^{4} . 5^{4} }{5^{10} . 2^{10} }$
=$\frac{5^{8} . (2^{2})^{4} }{5^{10} . 2^{10} }$
=$\frac{1}{5^{2} . 2^{2} }$
=$\frac{1}{ 25 . 4 }$
=$\frac{1}{ 100 }$
c)(-$\frac{10}{3}$)$^{5}$ . ($\frac{-6}{5}$)$^{4}$
=-$\frac{100000}{243}$ . -$\frac{81}{16}$
=-$\frac{4.25000}{9.27}$ . (-$\frac{9.9}{4.4}$)
=-$\frac{25000}{27}$ . (-$\frac{9}{4}$)
=-$\frac{6250.4}{9.3}$ . (-$\frac{9}{4}$)
=$\frac{6250}{3}$
d)(1+$\frac{2}{3}$-$\frac{1}{4}$).($\frac{4}{5}$-$\frac{3}{4}$)$^{2}$
=($\frac{12}{12}$+$\frac{8}{12}$-$\frac{3}{12}$).($\frac{16}{20}$-$\frac{15}{20}$)$^{2}$
=$\frac{17}{12}$.($\frac{1}{20}$)$^{2}$
=$\frac{17}{12}$.$\frac{1}{400}$
=$\frac{17}{4800}$
e)(0,25)$^{3}$.32
=($\frac{1}{4}$)$^{3}$.32
=($\frac{1}{64}$).32
=$\frac{32}{64}$
=$\frac{1}{2}$
f)(-0,125)$^{3}$.80$^{4}$
=(-$\frac{1}{8}$)$^{3}$.(8.10)$^{4}$
=-$\frac{1}{512}$.8$^{4}$.10$^{4}$
=-$\frac{1}{512}$.(2$^{3}$)$^{4}.(2.5)$^{4}$
=-$\frac{1}{512}$.2$^{12}$.2$^{4}$.5$^{4}$
=-$\frac{1}{512}$.2$^{16}$.5$^{4}$
=-$\frac{1}{512}$.65536.625
=-$\frac{1}{512}$.40960000
=-80000
g)$\frac{8^{2}.4^{5}}{2^{20}}$
=$\frac{(2^{3})^{2}.(2^{2})^{5}}{2^{20}}$
=$\frac{2^{6}.2^{10}}{2^{20}}$
=$\frac{2^{16}}{2^{20}}$
=$\frac{1}{2^{4}}$
=$\frac{1}{16}$
mình chỉ làm được đến phần g) nên mong bạn thông cảm cho mình nha!!
