Tính:
a.(3/7)^21 : (9/49)^6
b. 3+(6/7)^0+(1/2)^2: 2
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) Ta có: \(\dfrac{-5}{7}\left(\dfrac{14}{5}-\dfrac{7}{10}\right):\left|-\dfrac{2}{3}\right|-\dfrac{3}{4}\left(\dfrac{8}{9}+\dfrac{16}{3}\right)+\dfrac{10}{3}\left(\dfrac{1}{3}+\dfrac{1}{5}\right)\)
\(=\dfrac{-5}{7}\cdot\dfrac{3}{2}\cdot\dfrac{21}{10}-\dfrac{3}{4}\cdot\dfrac{56}{3}+\dfrac{10}{3}\cdot\dfrac{8}{15}\)
\(=\dfrac{-9}{4}-14+\dfrac{16}{9}\)
\(=\dfrac{-1621}{126}\)
b) Ta có: \(\dfrac{17}{-26}\cdot\left(\dfrac{1}{6}-\dfrac{5}{3}\right):\dfrac{17}{13}-\dfrac{20}{3}\left(\dfrac{2}{5}-\dfrac{1}{4}\right)+\dfrac{2}{3}\left(\dfrac{6}{5}-\dfrac{9}{2}\right)\)
\(=\dfrac{-17}{26}\cdot\dfrac{13}{17}\cdot\dfrac{-3}{2}-\dfrac{20}{3}\cdot\dfrac{3}{20}+\dfrac{2}{3}\cdot\dfrac{-33}{10}\)
\(=\dfrac{3}{4}-1-\dfrac{11}{5}\)
\(=-\dfrac{49}{20}\)
a) $\frac{3}{5} \times \frac{6}{7} = \frac{{3 \times 6}}{{5 \times 7}} = \frac{{18}}{{35}}$
b) $\frac{2}{9} \times \frac{{18}}{3} = \frac{{2 \times 18}}{{9 \times 3}} = \frac{{36}}{{27}} = \frac{4}{3}$
c) $\frac{5}{7} \times 12 = \frac{{5 \times 12}}{7} = \frac{{60}}{7}$
d) $21 \times \frac{2}{7} = \frac{{21 \times 2}}{7} = \frac{{42}}{7} = 6$
a, 5/-14. 7/-19=8/38
b, -15/4 .( 16/-25 )=12/5
c, 3/-10 .( -15/-2 )=
d, -5/7 . ( 21/-10 )=-9/4
e, 10/-3. (6/-5)==4
f, 21/-9 . ( -6/14 )=1
g, -10/9 . ( 36/20 )=-2
\(\left(\frac{3}{7}+\frac{1}{2}\right)^2=\left(\frac{13}{14}\right)^2=\frac{169}{196}\)
\(\frac{5^4\cdot20^4}{25^5\cdot4^5}=\frac{5^4\cdot4^4\cdot5^4}{5^5\cdot5^5.4^5}=\frac{1}{100}\)
\(\left(\frac{3}{7}\right)^{21}:\left(\frac{9}{49}\right)^6=\left(\frac{3}{7}\right)^{21}:\left[\left(\frac{3}{7}\right)^2\right]^6=\left(\frac{3}{7}\right)^{21}:\left(\frac{3}{7}\right)^{12}=\left(\frac{3}{7}\right)^9\)
\(3-\left(-\frac{6}{7}\right)^0+\left(\frac{1}{2}\right)^2:2\)
\(=3-1+\frac{1}{4}:2=3-1+\frac{1}{8}=\frac{17}{8}\)
a: \(=\dfrac{18+6}{27+6}=\dfrac{24}{33}=\dfrac{8}{11}\)
b: \(=\dfrac{21\cdot7\cdot11}{3\cdot11\cdot4}=\dfrac{147}{12}=\dfrac{49}{4}\)