Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a, \(\dfrac{20^5.5^{10}}{100^5}=\dfrac{20^5.5^{10}}{\left(20.5\right)^5}=\dfrac{20^5.5^{10}}{20^5.5^5}=5^5\)
b,\(\dfrac{\left(0,9\right)^5}{\left(0,3\right)^6}=\dfrac{\left(0,3.3\right)^5}{\left(0,3\right)^6}=\dfrac{\left(0,3\right)^5.3^5}{\left(0,3\right)^6}=\dfrac{3^5}{\left(0,3\right)}\)
\(a,=5\cdot0,6-10\cdot0,2=3-2=1\\ b,=\dfrac{1}{9}:\left(\dfrac{1}{30}\right)^2=\dfrac{1}{9}:\dfrac{1}{900}=\dfrac{1}{9}\cdot900=100\)
a: \(=6+\dfrac{4}{5}-1-\dfrac{2}{3}-3-\dfrac{4}{5}\)
\(=2-\dfrac{2}{3}=\dfrac{4}{3}\)
b: \(=7+\dfrac{5}{9}-2-\dfrac{3}{4}-3-\dfrac{5}{9}=2-\dfrac{3}{4}=\dfrac{5}{4}\)
c: =6+7/7-1-3/4-2-5/7
=3+2/7-3/4
=84/28+8/28-21/28
=84/28-13/28
=71/28
\(\dfrac{8^{14}}{4^4.64^5}=\dfrac{\left(2^3\right)^{14}}{\left(2^2\right)^4.\left(2^5\right)^5}=\dfrac{2^{42}}{2^8.2^{25}}=2^{42-\left(8+25\right)}=2^9\)
\(\dfrac{9^{10}.27^7}{81^7.3^{15}}=\dfrac{\left(3^2\right)^{10}.\left(3^3\right)^7}{\left(3^4\right)^7.3^{15}}=\dfrac{3^{20}.3^{21}}{3^{28}.3^{15}}=\dfrac{3^{20+21}}{3^{28+15}}=\dfrac{3^{41}}{3^{41}.3^2}=\dfrac{1}{3^2}=\dfrac{1}{9}\)
\(A=\dfrac{2^{12}\cdot3^5-2^{12}\cdot3^4}{2^{12}\cdot3^6+2^{12}\cdot3^5}-\dfrac{5^{10}\cdot7^3-5^{10}\cdot7^4}{5^9\cdot7^3+5^9\cdot7^3\cdot2^3}\)
\(=\dfrac{3^4\left(3-1\right)}{3^5\left(3+1\right)}-\dfrac{5^{10}\cdot7^3\left(1-7\right)}{5^9\cdot7^3\cdot9}\)
\(=\dfrac{1}{3\cdot2}-\dfrac{1}{5}\cdot\dfrac{-6}{9}=\dfrac{1}{6}+\dfrac{6}{45}=\dfrac{45+36}{270}=\dfrac{81}{270}=\dfrac{3}{10}\)
Để tính giá trị của biểu thức $A = \frac{1}{5^2-1} \cdot \frac{1}{6^2-1} \cdot \frac{1}{7^2-1} \cdots \frac{1}{2025^2-1}$, ta có thể sử dụng công thức $a^2-b^2=(a+b)(a-b)$ để đơn giản hóa các mẫu số trong từng phân số. Ta có:
\begin{align*}
A &= \frac{1}{(5+1)(5-1)} \cdot \frac{1}{(6+1)(6-1)} \cdot \frac{1}{(7+1)(7-1)} \cdots \frac{1}{(45+1)(45-1)} \
&= \frac{1}{4 \cdot 6} \cdot \frac{1}{5 \cdot 7} \cdot \frac{1}{6 \cdot 8} \cdots \frac{1}{46 \cdot 44} \
&= \frac{1}{4} \cdot \frac{1}{5} \cdot \frac{1}{7} \cdot \frac{1}{8} \cdots \frac{1}{44} \cdot \frac{1}{46} \
&= \frac{1}{4} \cdot \frac{1}{46} \cdot \frac{1}{5} \cdot \frac{1}{44} \cdot \frac{1}{7} \cdot \frac{1}{42} \cdots \frac{1}{23} \cdot \frac{1}{21} \
&= \frac{1}{2} \cdot \frac{1}{23} \cdot \left( \frac{1}{2} - \frac{1}{23} \right) \cdot \frac{1}{3} \cdot \left( \frac{1}{3} - \frac{1}{22} \right) \cdots \frac{1}{20} \cdot \left( \frac{1}{20} - \frac{1}{25} \right) \
&= \frac{1}{2} \cdot \frac{1}{23} \cdot \frac{21}{22} \cdot \frac{1}{3} \cdot \frac{19}{22} \cdots \frac{1}{20} \cdot \frac{5}{25} \
&= \frac{1}{2} \cdot \frac{21}{23} \cdot \frac{19}{22} \cdot \frac{17}{20} \cdots \frac{3}{5} \cdot \frac{1}{5} \
&= \frac{21 \cdot 19 \cdot 17 \cdots 3}{2 \cdot 23 \cdot 22 \cdots 5} \cdot \frac{1}{5} \
&= \frac{21 \cdot 19 \cdot 17 \cdots 3}{2 \cdot 23 \cdot 22 \cdots 6} \
\end{align*}
Vậy giá trị của biểu thức $A$ là $\frac{21 \cdot 19 \cdot 17 \cdots 3}{2 \cdot 23 \cdot 22 \cdots 6}$.
Lời giải:
1.
$(\frac{5}{6})^{10}.(\frac{3}{10})^{10}=(\frac{5}{6}.\frac{3}{10})^{10}=(\frac{1}{4})^{10}$
$=\frac{1}{4^{10}}$
2.
$(\frac{4}{7})^{19}: (\frac{-12}{35})^{19}=(\frac{4}{7}: \frac{-12}{35})^{19}=(\frac{-5}{3})^{19}$
3.
$(\frac{-3}{7})^7:\frac{-3}{5}=\frac{(-3)^7}{7^7}.\frac{5}{-3}=\frac{5.(-3)^6}{7^7}=\frac{5.3^6}{7^7}$
A) \(\dfrac{4^5.4^2}{16^4}=\dfrac{4^7}{\left(2^4\right)^4}=\dfrac{2^{14}}{2^{16}}=\dfrac{1}{4}\)
b)\(\dfrac{2^8.9^4}{6^6.8^3}=\dfrac{2^8.\left(3^2\right)^4}{2^6.3^6.\left(2^3\right)^3}=\dfrac{2^8.3^8}{2^{15}.3^6}=\dfrac{9}{128}\)
c) \(\dfrac{6^3+3.6^2+3^3}{-13}=\dfrac{2^3.3^3+3.2^2.3^2+3^3}{-13}=\dfrac{2^3.3^3+3^3.2^2+3^3}{-13}=\dfrac{3^3.\left(2^3+2^2+1\right)}{-13}=\dfrac{3^3.13}{-13}=-9\)
a, 205.510/1005
=205.55.55/1005
=1005.55/1005
=55
=3125
b, (0,9)5/(0,3)6
=(0,3.3)5/0,36
=0,55.35/0,36
=35/0,3
=810
c, 63+3.62+33/-13
=(2.3)3+3.(3.2)2+33/-13
=23.33+3.32.22+33/-13
=33.23+33.22+33/-13
=33(23+22+1)/-13
=27.13/-13
=-27
d, 46.95+69.120/84.312-611
=(22)6.(32)5+(2.3)9.3.23.5/(23)4.312-(2.3)11
=212.310+29.39.3.23.5/212.312-211.311
=212.310+212.310.5/211.311.2.3-211.311
=212.310.(1+5)/211.311(6-1)
=212.310.6/211.311.5
=2.6/3.5
=12/15
=4/5
GIÚP MÌNH VỚI MN ƠIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
\(A=\dfrac{\left(20.5\right)^5.5^5}{100^5}=\dfrac{100^5.3125}{100^5}=3125\)
\(B=\dfrac{\left(0,3.3\right)^5}{\left(0,3\right)^5.0,3}=\dfrac{\left(0,3\right)^5.3^5}{\left(0,3\right)^5.0,3}=\dfrac{3^5}{0,3}=810\)