\(\frac{6}{5}:3\)
\(\frac{15}{16}:25\)
Tính: a ) \(-3\frac{3}{4}+\frac{-10}{25}+\frac{-6}{12}\)
b) \(-0,6-\frac{-4}{9}-\frac{16}{15}\)
c ) \(\frac{7}{12}-\left(-\frac{1}{15}\right)-\frac{5}{6}+\frac{2}{3}+\left(-\frac{1}{5}\right)\)
Tính:
a) \(-3\frac{3}{4}+\left(-\frac{10}{25}\right)+\left(-\frac{6}{12}\right)\)
\(=\left(-\frac{15}{4}\right)+\left(-\frac{10}{25}\right)+\left(-\frac{6}{12}\right)\)
\(=\left(-\frac{83}{20}\right)+\left(-\frac{6}{12}\right)\)
\(=-\frac{93}{20}.\)
b) \(-0,6-\left(-\frac{4}{9}\right)-\frac{16}{15}\)
\(=\left(-\frac{3}{5}\right)-\left(-\frac{4}{9}\right)-\frac{16}{15}\)
\(=\left(-\frac{7}{45}\right)-\frac{16}{15}\)
\(=-\frac{11}{9}.\)
Chúc bạn học tốt!
bài 1 : tính phân số:
a) \(\frac{5}{7}+\frac{4}{9}=?;\frac{4}{5}-\frac{2}{3}=?;\frac{9}{11}+\frac{3}{8}=?;\frac{16}{25}-\frac{2}{5}=?\)=?
b)\(5+\frac{3}{5}=?;10-\frac{9}{16}=?;\frac{2}{3}-\left(\frac{1}{6}+\frac{1}{8}\right)=?\)
c)\(\frac{5}{7}+\frac{7}{6}=?;\frac{7}{12}+\frac{17}{18}=?;\frac{9}{8}+\frac{15}{32}=?;4+\frac{35}{45}=?\)
d)\(\frac{11}{4}-\frac{15}{16}=?;\frac{5}{6}-\frac{5}{8}=?;\frac{196}{64}-2=?;3-\frac{13}{9}=?\)
e)\(\frac{8}{5}+\frac{7}{6}+\frac{5}{9}-2=?;3-\frac{5}{6}-\frac{4}{9}+\frac{32}{24}=?\)
a)\(\dfrac{5}{7}+\dfrac{4}{9}=\dfrac{45}{63}+\dfrac{28}{63}=\dfrac{73}{63}\) ; \(\dfrac{9}{11}+\dfrac{3}{8}=\dfrac{72}{88}+\dfrac{33}{88}=\dfrac{105}{88}\)
\(\dfrac{4}{5}-\dfrac{2}{3}=\dfrac{12}{15}-\dfrac{10}{15}=\dfrac{2}{15}\); \(\dfrac{16}{25}-\dfrac{2}{5}=\dfrac{16}{25}-\dfrac{10}{25}=\dfrac{6}{25}\)
tính giá trị biểu thức
\(A=\frac{-378.132+189.64}{15+18+21+......+45+48}\)
\(B=1,4.\frac{15}{14}-\left(\frac{4}{5}+\frac{2}{5}\right):2\frac{1}{5}-\frac{\frac{73}{77}+\frac{73}{165}+\frac{73}{285}}{\frac{25}{24}+\frac{15}{180}+\frac{20}{285}}\)
\(C=\frac{7+\frac{7}{12}-\frac{7}{144}+\frac{7}{60}}{5+\frac{6}{12}-\frac{5}{144}}.\frac{\frac{3}{4}-\frac{3}{16}+\frac{3}{64}-\frac{3}{256}}{1-\frac{1}{4}+\frac{1}{16}-\frac{1}{34}}-\frac{1}{20}\)
BÀI 1 :
\(\left(\frac{37}{13}+\frac{25}{16}\right):\frac{3}{5}-\left(\frac{9}{16}-\frac{15}{13}\right):\frac{3}{5}\)
\(\left(\frac{37}{13}+\frac{25}{16}-\frac{9}{16}+\frac{15}{13}\right)\div\frac{3}{5}\)
\(=\left(4+1\right)\div\frac{3}{5}\)
\(=5\div\frac{3}{5}\)
\(=\frac{25}{3}\)
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=\(\left(-\frac{3}{2}\right)^2+|-\frac{5}{6}|-1\frac{1}{2}:6\)
\(A=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}=\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-\frac{64}{34}+\frac{14}{21}=\left(\frac{15}{34}+\frac{9}{34}-\frac{64}{34}\right)+\left(\frac{7}{21}+\frac{14}{21}\right)=\frac{30}{34}+\frac{21}{21}=\frac{15}{17}+1=\frac{32}{17}\)
Tính nhanh : \(\frac{1}{8}\div12,5\%+\left(\frac{1\times2\times3+6\times4\times2}{5\times3\times1+5\times15\times25}+\frac{1}{2}\div50\%\right)-\left(\frac{1}{16}\div6,25\%+\frac{3+2+1+2+4+6}{1+3+5+25+15+5}\right)-\frac{1}{4}\div25\%\)
\(\frac{1}{8}=12,5\%\) ; \(\frac{1}{16}=6,25\%\) ; \(\frac{1}{2}=50\%\) ; \(\frac{1}{4}=25\%\)
Thay vào trên mà tính.
= \(1+\left(\frac{3\left(1x2+2x4x2\right)}{3\left(5+5x3x25\right)}+1\right)-\left(1+\frac{18}{54}\right)-1\) = \(\frac{18}{380}-\frac{18}{54}\)
Tìm các số x,y,z biết rằng
\(\frac{x-2}{x-1}=\frac{x+4}{x+7}\)
\(\frac{10}{x-5}=\frac{6}{y-9}=\frac{14}{z-21}\) và xyz= 6720
\(\frac{2x-3}{2x-5}=\frac{2x+5}{2x+8}\)
\(\frac{x+16}{9}=\frac{y-25}{16}=\frac{z+9}{25}\) và \(2x^3-1=15\)
4.Tinh
a,\(\frac{4^{30}.3^{43}}{2^{53}.27^{15}}\)
b,\(\frac{\left(-27\right)^{10}.16^{25}}{6^{30}.\left(-32\right)^{15}}\)
c,\(\left(\frac{-2}{17}\right)^3.\left(\frac{-17}{35}\right)^3.\left(\frac{35}{3}\right)^3\)
d,\(\frac{3^{31}.25^8-9^{14}.5^{15}}{27^{10}.5^{15}-3^{30}.5^{17}}\)
e,\(2^{^2}+4^{^2}+6^2+..........+24^2\left(1^2+2^2+3^2+....+12^2=650\right)\)
a) \(3\frac{14}{19}+\frac{13}{17}+\frac{35}{43}+6\)
b) \(\frac{\frac{15}{12}+\frac{3}{4}-1}{3-\frac{5}{6}+\frac{2}{3}}+\frac{\frac{16}{5}+\frac{16}{7}-\frac{16}{9}}{\frac{17}{5}+\frac{17}{7}-\frac{17}{9}}\)
\(3\frac{14}{19}+\frac{13}{17}+\frac{35}{43}+6\)
\(=\frac{71}{19}+\frac{13}{17}+\frac{35}{43}+6\)
\(=\frac{1454}{323}+\frac{35}{43}+6\)
\(=5,...+6\)
\(=11,...\)
\(Bai2a\)\(A=\frac{\sqrt{3}-\sqrt{6}}{1-\sqrt{2}}-\frac{2+\sqrt{8}}{1+\sqrt{2}}\)
\(=\frac{\sqrt{3}\left(1-\sqrt{2}\right)}{1-\sqrt{2}}-\frac{2\left(1+\sqrt{2}\right)}{1+\sqrt{2}}\)
\(=\sqrt{3}-2\)
\(VayA=\sqrt{3}-2\)
Tính:
\(\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+\frac{1}{5}-\frac{1}{6}+\frac{1}{7}-\frac{1}{8}+.....+\frac{1}{2015}-\frac{1}{2016}+\frac{1}{2017}.\)
\(\frac{5-\frac{5}{3}+\frac{5}{9}-\frac{5}{27}}{8-\frac{8}{3}+\frac{8}{9}-\frac{8}{27}}:\frac{15-\frac{15}{11}+\frac{15}{121}}{16-\frac{16}{11}+\frac{16}{121}}.\)