Tính giá trị biểu thức :
\(M=\sqrt{\left(0,04\right)^{-1,5}-\left(0,125\right)^{\frac{-2}{3}}}\)
Rút gọn các biểu thức sau :
a) \(A=\left(0,04\right)^{-1,5}-\left(0,125\right)^{\frac{-2}{3}}\)
b) \(B=\left(6^{\frac{-2}{7}}\right)^{-7}-\left[\left(\left(0,2\right)^{0,75}\right)^{-4}\right]\)
c) \(C=\frac{a^{\sqrt{5}+3}.a^{\sqrt{5}\left(\sqrt{5}-1\right)}}{\left(a^{2\sqrt{2}-1}\right)^{2\sqrt{2}+1}}\)
d) \(D=\left(a^{\frac{1}{2}}-b^{\frac{1}{2}}\right)^2:\left(b-2b\sqrt{\frac{b}{a}}+\frac{b^2}{a}\right)\left(a,b>0\right)\)
a) \(A=\left[\left(\frac{1}{5}\right)^2\right]^{\frac{-3}{2}}-\left[2^{-3}\right]^{\frac{-2}{3}}=5^3-2^2=121\)
b) \(B=6^2+\left[\left(\frac{1}{5}\right)^{\frac{3}{4}}\right]^{-4}=6^2+5^3=161\)
c) \(C=\frac{a^{\sqrt{5}+3}.a^{\sqrt{5}\left(\sqrt{5}-1\right)}}{\left(a^{2\sqrt{2}-1}\right)^{2\sqrt{2}+1}}=\frac{a^{\sqrt{5}+3}.a^{5-\sqrt{5}}}{a^{\left(2\sqrt{2}\right)^2-1^2}}\)
\(=\frac{a^{\sqrt{5}+3+5-\sqrt{5}}}{a^{8-1}}=\frac{a^8}{a^7}=a\)
d) \(D=\left(a^{\frac{1}{2}}-b^{\frac{1}{2}}\right)^2:\left(b-2b\sqrt{\frac{b}{a}}+\frac{b^2}{a}\right)\)
\(=\left(\sqrt{a}-\sqrt{b}\right)^2:b\left[1-2\sqrt{\frac{b}{a}}+\left(\sqrt{\frac{b}{a}}\right)^2\right]\)
\(=\left(\sqrt{a}-\sqrt{b}\right)^2:b\left(1-\sqrt{b}a\right)^2\)
Tính giá trị biểu thức:
\(\frac{\left(0,125\right)^5.\left(2,4\right)^5}{\left(-0,3\right)^5.\left(0,01\right)^3}\)
\(=\dfrac{3^5}{-\left(0.003\right)^3\cdot0.09}=-10^{11}\)
Tính giá trị biểu thức :
\(M=\left(\frac{1}{4}\right)^{-\frac{3}{2}}-2\left(\frac{125}{27}\right)^{-\frac{2}{3}}+2^{\left(\sqrt{6}+\sqrt{2}\right)\sqrt{2-\sqrt{3}}}\)
Ta có:
\(\left(\frac{1}{4}\right)^{-\frac{3}{2}}=8\) ;
\(2\left(\frac{125}{27}\right)^{-\frac{2}{3}}=2.\frac{9}{25}=\frac{18}{25}\) ;
\(\left(\sqrt{6}+\sqrt{2}\right)\sqrt{2-\sqrt{3}}=2\Rightarrow2^{\left(\sqrt{6}+\sqrt{2}\right)\sqrt{2-\sqrt{3}}}=2^2=4\)
\(\Rightarrow M=8-\frac{18}{25}+4=4\frac{18}{25}\)
Ta có \(\left(\sqrt{6}+\sqrt{2}\right)\sqrt{2-\sqrt{3}}=\left(\sqrt{3}+1\right)\sqrt{4-2\sqrt{3}}=\left(\sqrt{3}+1\right)\left(\sqrt{3}-1\right)=2\)
Nên \(B=2^{2\left(-\frac{3}{2}\right)}-2\left(\frac{5}{3}\right)^{3\left(-\frac{2}{3}\right)}+2^2=2^3-2\left(\frac{3}{5}\right)^2+4=\frac{282}{25}\)
Tính giá trị của biểu thức sau.
\(\frac{\left(0,125\right)^5.\left(2,4\right)^5}{\left(-0,3\right)^5.\left(0,01\right)^3}\)
Tính giá trị của biểu thức:
\(a)\frac{\left(0,125\right)^5.\left(2,4\right)^5}{\left(-0,3\right)^5.\left(0.01\right)^3}\)
\(b)\left(-2\frac{3}{4}+\frac{1}{2}\right)^2\)
a)=-1000000
b)=81/56
chúc bạn học tốt
1/Cho \(x+y+z+\sqrt{xyz}=4\)
Tính giá trị biểu thức \(T=\sqrt{x\left(4-y\right)\left(4-z\right)}+\sqrt{y\left(4-x\right)\left(4-z\right)}+\sqrt{z\left(4-x\right)\left(4-y\right)}-\sqrt{xyz}\)
2/Cho \(x=\sqrt[3]{4+2\sqrt{2}}+\sqrt[3]{4-2\sqrt{2}}\)
Tính giá trị biểu thức \(F=\left(x^3-6x-10\right)^{2019}\)
3/Cho \(x=\sqrt{\frac{1}{2\sqrt{3}-2}-\frac{3}{2\sqrt{3}+2}}\)
Tính giá trị biểu thức \(P=x^2+\frac{x-1}{2}\)
4/Cho \(x=\sqrt{28-10\sqrt{3}}\)
Tính giá trị biểu thức \(F=\frac{2x^4-21x^3+55x^2-32x-4012}{x^2-10x+20}\)
Tính giá trị biểu thức :
\(M=\frac{7\ln\left(3+2\sqrt{2}\right)-64\ln\left(\sqrt{2}+1\right)-50\ln\left(\sqrt{2}-1\right)+2}{lg125^{-1}-lg0.8+6lg\sqrt[3]{0.4}+4lg50}\)
Ta có :
\(M=\frac{7\ln\left(\sqrt{2}+1\right)^2-64\ln\left(\sqrt{2}+1\right)-50\ln\left(\sqrt{2}+1\right)^{-1}+2}{-3lg5-lg\left(10^{-1}.2^3\right)+6lg\left(10^{-\frac{1}{3}}.2^{\frac{2}{3}}\right)+4lg\left(10.5\right)}\)
\(=\frac{2}{lg5+1-3lg2-2+4lg2+4}=\frac{1}{2}\)
Tính giá trị biểu thức :
\(A=\left(3\sqrt{3}\right)^{\frac{4}{3}}+\left(\frac{1}{16}\right)^{\frac{3}{4}}+2\left(\frac{8}{27}\right)^{\frac{2}{3}}\)
\(A=\left(3\sqrt{3}\right)^{\frac{4}{3}}+\left(\frac{1}{16}\right)^{\frac{3}{4}}+2\left(\frac{8}{27}\right)^{\frac{2}{3}}\)
\(A=\left(3\sqrt{3}\right)^{\frac{4}{3}}+55+\frac{32}{3}\)
\(A=\left(3\sqrt{3}\right)^{\frac{4}{3}}+\frac{197}{3}\)
\(A=243+\frac{197}{3}\)
\(A=\frac{926}{3}\)
Ta có \(A=3^{\frac{3}{2}.\frac{4}{3}}+\left(\frac{1}{2}\right)^{4.\frac{3}{4}}+2\left(\frac{2}{3}\right)^{3.\frac{2}{3}}=3^2+\left(\frac{1}{2}\right)^3+2\left(\frac{2}{3}\right)^2=\frac{721}{72}\)
Ta có:
\(A=\left(3\sqrt{3}\right)^{\frac{4}{3}}+\left(\frac{1}{6}\right)^{\frac{3}{4}}+2\left(\frac{8}{27}\right)^{\frac{2}{3}}=9+\frac{3}{32}+\frac{4}{9}=9\frac{155}{288}\)
Tính giá trị của các biểu thức sau:
a)\(\frac{6^2.6^3}{3^5}\) b)\(\frac{25^2.4^2}{5^5.\left(-2\right)^5}\) c)\(\frac{\left(0,125\right)^5.\left(2,4\right)^5}{\left(-0,3\right)^5.\left(0,01\right)^3}\) d)\(\left(-2\frac{3}{4}+\frac{1}{2}\right)^2\)