Tính :
a) \(\left(\dfrac{1}{16}\right)^{-\dfrac{3}{4}}+810000^{0,25}-\left(7\dfrac{19}{32}\right)^{\dfrac{1}{5}}\)
b) \(\left(0,001\right)^{-\dfrac{1}{3}}-2^{-2}.64^{\dfrac{2}{3}}-8^{-1\dfrac{1}{3}}\)
c) \(27^{\dfrac{2}{3}}-\left(-2\right)^{-2}+\left(3\dfrac{3}{8}\right)^{-\dfrac{1}{3}}\)
d) \(\left(-0,5\right)^{-4}-625^{0,25}-\left(2\dfrac{1}{4}\right)^{-1\dfrac{1}{2}}\)
Tính:
\(a)\ 9^{\dfrac{2}{5}}.27^{\dfrac{2}{5}}\)
\(b)\ 144^{\dfrac{3}{4}}:9^{\dfrac{3}{4}}\)
\(c)\ (\dfrac{1}{16})^{-0,75}+(0,25)^{\dfrac{-5}{2}}\)
\(d)\ (0,04)^{-1,5}-(0,125)^{\dfrac{-2}{3}} \)
Cho a, b là những số thực dương. Rút gọn các biểu thức sau:
\(a)\ \dfrac{a^{\dfrac{4}{3}}(a^{\dfrac{-1}{3}}+a^{\dfrac{2}{3}})}{a^{\dfrac{1}{4}}(a^{\dfrac{3}{4}}+a^{\dfrac{-1}{4}})}\)
\(b)\ \dfrac{b^{\dfrac{1}{5}} (\sqrt[5]{b^4}-\sqrt[5]{b^{-1}})}{b^{\dfrac{2}{3}}(\sqrt[3]{b}-\sqrt[3]{b^{-2}})}\)
\(c)\ \dfrac{a^{\dfrac{1}{3}}b^{\dfrac{-1}{3}}-a^{\dfrac{-1}{3}}b^{\dfrac{1}{3}}}
{\sqrt[3]{a^2}-\sqrt[3]{b^2}}\)
\(d)\ \dfrac{a^{\dfrac{1}{3}} \sqrt{b}+b^{\dfrac{1}{3}} \sqrt{a}}
{\sqrt[6]{a}+\sqrt[6]{b}}\)
Cho a và b là các số dương. Đơn giản các biểu thức sau :
a) \(\dfrac{a^{\dfrac{4}{3}}\left(a^{-\dfrac{1}{3}}+a^{\dfrac{2}{3}}\right)}{a^{\dfrac{1}{4}}\left(a^{\dfrac{3}{4}}+a^{-\dfrac{1}{4}}\right)}\)
b) \(\dfrac{a^{\dfrac{1}{3}}\sqrt{b}+b^{\dfrac{1}{3}}\sqrt{a}}{\sqrt[6]{a}+\sqrt[6]{b}}\)
c) \(\left(\sqrt[3]{a}+\sqrt[3]{b}\right)\left(a^{\dfrac{2}{3}}+b^{\dfrac{2}{3}}-\sqrt[3]{ab}\right)\)
d) \(\left(a^{\dfrac{1}{3}}+b^{\dfrac{1}{3}}\right):\left(2+\sqrt[3]{\dfrac{a}{b}}+\sqrt[3]{\dfrac{b}{a}}\right)\)
\(\sqrt[3]{\dfrac{2}{3}\sqrt[3]{\dfrac{2}{3}\sqrt{\dfrac{2}{3}}}}\)
Cho a;b;c >=0 thỏa mãn \(a^2+b^2+c^2=3\)
\(CMR:\dfrac{a}{b+2}+\dfrac{b}{c+2}+\dfrac{c}{a+2}\le1\)
chứng tỏ rằng \(\dfrac{1}{6}\)<\(\dfrac{1}{5^{ }2}\)+\(\dfrac{1}{6^{ }2}\)...+\(\dfrac{1}{100^{ }2}\)<\(\dfrac{1}{4}\)
Hãy so sánh mỗi số sau với 1 :
a) \(2^{-2}\)
b) \(\left(0,013\right)^{-1}\)
c) \(\left(\dfrac{2}{7}\right)^5\)
d) \(\left(\dfrac{1}{2}\right)^{\sqrt{3}}\)
e) \(\left(\dfrac{\pi}{4}\right)^{\sqrt{5}-2}\)
g) \(\left(\dfrac{1}{3}\right)^{\sqrt{8}-3}\)
Viết các số sau theo thứ tự tăng dần:
\(a)\ 1^{3,75};\ 2^{-1};\ (\dfrac{1}{2})^{-3}\)
\(b)\ 98^0;\ (\dfrac{3}{7})^{-1};\ 32^{\dfrac{1}{5}}\)
