\(\left(-3\right)^2\cdot\frac{1}{3}-\sqrt{49}+\left(-5\right):\sqrt{25}\)
\(4\frac{3}{4}+\frac{5}{19}-\frac{3}{4}+1.5+\frac{14}{9}\)
\(\frac{x}{3}=\frac{y}{2}\)và x+y=10
\(\frac{1}{3}-0.84-0.16+\frac{2}{3}+\frac{2}{11}\)
\(\frac{x}{3}=\frac{y}{3}\) và x+y=10 A)
\(4\frac{3}{4}+\frac{5}{19}-\frac{3}{4}+1.5+\frac{14}{9}\) B)
\(\left(-3\right)^2\cdot\frac{1}{3}-\sqrt{49}+\left(-5\right)^3:\sqrt{25}\) C)
\(\frac{1}{3}-0.84-0.16+\frac{2}{3}+\frac{2}{11}\) D)
a: Vì x/3=y/3 nên x=y
mà x+y=10
nên x=y=10/2=5
b: \(=\left(4+\dfrac{3}{4}-\dfrac{3}{4}\right)+\left(\dfrac{5}{19}+\dfrac{14}{19}\right)+1.5=5.5+1=6.5\)
c: \(=9\cdot\dfrac{1}{3}-7+\left(-125\right):5=3-7-25=-29\)
\(\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{35}\right)\cdot\left(-\frac{4}{15}\right)}{\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{5}\right)\cdot\frac{5}{7}}\)
\(A=\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{35}\right)\cdot\left(-\frac{4}{15}\right)}{\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{2}\right)\cdot\frac{5}{7}}\)
Bài 1: Thực hiện phép tính:
a,\(\left(\frac{-3}{4}+\frac{2}{7}\right):\frac{2}{7}+\left(\frac{-1}{4}+\frac{5}{7}\right):\frac{2}{3}\)
b,\(\left(-\frac{1}{3}\right)^2\cdot\frac{4}{11}+\frac{7}{11}\cdot\left(-\frac{1}{3}\right)^2\)
c, \(\left(-\frac{1}{7}\right)^0-2\frac{4}{9}\cdot\left(\frac{2}{3}\right)^2\)
d,\(\frac{2^7\cdot9^2}{3^3\cdot2^5}\)
e,\(\left(\frac{1}{3}-\frac{5}{6}\right)^2+\frac{5}{6}:2\)
f,\(\left(9\frac{2}{4}:5,2+3.4\cdot2\frac{7}{34}\right):\left(-1\frac{9}{16}\right)\)
g,\(\sqrt{25}-3\sqrt{\frac{4}{9}}\)
h,\(\left(-2\right)^2+\sqrt{36}-\sqrt{9}+\sqrt{25}\)
i,\(\left(-\frac{1}{2}\right)^4+\left|-\frac{2}{3}\right|-2007^0\)
k,\(\left(-2\right)^3+\frac{1}{2}:\frac{1}{8}-\sqrt{25}+\left|-64\right|\)
m,\(\left(-3\right)^2\cdot\frac{1}{3}-\sqrt{49}+\left(-5\right)^3:\sqrt{25}\)
n,\(\frac{\sqrt{3^2+\sqrt{39^2}}}{\sqrt{91^2}-\sqrt{\left(-7\right)^2}}\)
giải hệ phương trình: A, \(\frac{1}{x}+\frac{1}{y}=9\) và \(\left(\frac{1}{\sqrt[3]{x}}+\frac{1}{\sqrt[3]{y}}\right)\cdot\left(\frac{1}{\sqrt[3]{x}}+1\right)\cdot\left(\frac{1}{\sqrt[3]{y}}+1\right)=18\)
B,\(3x^2-y=0\) và \(\left(\sqrt{5x^3-4}+2\sqrt[3]{7x^2-1}\right)\cdot\frac{y+4}{3}=2\cdot\left(y+19\right)\)
A=\(\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\)
B=\(16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
C=\(25\cdot\left(-\frac{1}{3}\right)^3+\frac{1}{5}-2\cdot\left(-\frac{1}{2}\right)^2-\frac{1}{2}\)
D=\(\left(-2\right)^3\cdot\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
E=\(5\sqrt{16}-4\sqrt{9}+\sqrt{25}-0,3\sqrt{400}\)
F=\(\left(-\frac{3}{2}\right)^2+|-\frac{5}{6}|-1\frac{1}{2}:6\)
\(A=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-\frac{64}{34}+\frac{14}{21}=\left(\frac{15}{34}+\frac{9}{34}-\frac{64}{34}\right)+\left(\frac{7}{21}+\frac{14}{21}\right)=\frac{30}{34}+\frac{21}{21}=\frac{15}{17}+1=\frac{32}{17}\)
Cho x =\(\frac{\left(\frac{3}{10}-\frac{4}{15}-\frac{7}{20}\right)\cdot\frac{5}{19}}{\left(\frac{1}{14}+\frac{1}{7}+\frac{3}{35}\right)\cdot\frac{-4}{3}}\)
Tính P=\(\sqrt{120\cdot x+39}\)
Tính nhanh:
\(\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{25}\right).\left(-\frac{4}{15}\right)}{\:\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{5}\right).\left(\frac{5}{7}\right)}\)
\(\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{35}\right)\times\left(\frac{-4}{15}\right)}{\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{5}\right)\times\frac{5}{7}}\)
\(\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{35}\right)\cdot\left(\frac{-4}{15}\right)}{\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{5}\right)\cdot\frac{5}{7}}\)
\(=-\frac{\left(\frac{1}{14}-\frac{\sqrt{2}}{7}+\frac{3\sqrt{2}}{35}\right)\cdot\frac{4}{15}}{\left(\frac{1}{10}+\frac{3\sqrt{2}}{25}-\frac{\sqrt{2}}{5}\right)\cdot\frac{5}{7}}\)
\(=-\frac{\frac{4}{15}\cdot\frac{5-4\sqrt{2}}{70}}{\frac{5}{7}\cdot\frac{5-4\sqrt{2}}{50}}\)
\(=-\frac{4\left(5-4\sqrt{2}\right)}{15\left(5-4\sqrt{2}\right)}\)
\(=-\frac{4}{15}\)