bài 1:
\(1)\frac35\cdot\frac{7}{12}-\frac25=\frac{7}{20}-\frac{8}{20}=-\frac{1}{20}\)
\(2)\frac35-\left(-\frac47\right)\cdot\left(-\frac14\right)=\frac35-\frac17=\frac{21}{35}-\frac{5}{35}=\frac{16}{35}\)
\(3)-\frac45+18\cdot\left(-\frac13\right)^2=-\frac45+18\cdot\frac19=-\frac45+\frac{10}{5}=\frac65\)
\(4)\frac{-3}{2}+\frac{-14}{5}\cdot\frac{10}{7}=-\frac32+\frac{-8}{2}=-\frac{11}{2}\)
\(5)\left(\right.\frac{-1}{5})^2+9\cdot\left(-\frac23\right)^2=\frac{1}{25}+9\cdot\frac49=\frac{1}{25}+\frac{100}{25}=\frac{101}{25}\)
\(6)\left(\frac15\right)^2+\left(1-\frac32\right)^2:1\frac13-\frac56=\frac{1}{25}+\frac14\cdot\frac34-\frac56\)
\(=\frac{1}{25}+\frac{3}{16}-\frac56=\frac{48}{1200}+\frac{225}{1200}-\frac{1000}{1200}=-\frac{727}{1200}\)
bài 2:
\(1)\left(\frac49+\frac37\right)-\left(\frac37-\frac59\right)=\frac49+\frac37-\frac37+\frac59\)
\(=\left(\frac49+\frac59\right)+\left(\frac37-\frac37\right)=1+0=1\)
\(2)-\left(\frac{55}{27}-\frac{21}{5}\right)+\left(\frac{55}{27}-\frac{-4}{5}\right)=-\frac{55}{27}+\frac{21}{5}+\frac{55}{27}+\frac45\)
\(=\left(\frac{55}{27}-\frac{55}{27}\right)+\left(\frac{21}{5}+\frac45\right)=0+5=5\)
\(3)\frac37\cdot\frac58+\frac37\cdot\frac{11}{8}=\frac37\cdot\left(\frac58+\frac{11}{8}\right)=\frac37\cdot\frac{16}{8}=\frac37\cdot2=\frac67\)
\(4)\frac38\cdot20\frac34+\frac38\cdot19\frac14=\frac38\cdot\frac{83}{4}+\frac38\cdot\frac{77}{4}\)
\(=\frac38\cdot\left(\frac{83}{4}+\frac{77}{4}\right)=\frac38\cdot\frac{160}{4}=\frac38\cdot40=3\cdot5=15\)
bài 3:
\(1)\left\lbrack\left(\frac12+\frac13\right)\cdot\frac35+\frac{3}{10}\right\rbrack:\frac45=\left\lbrack\left(\frac36+\frac26\right)\cdot\frac35+\frac{3}{10}\right\rbrack\cdot\frac54\)
\(=\left\lbrack\frac56\cdot\frac35+\frac{3}{10}\right\rbrack\cdot\frac54=\left\lbrack\frac{5}{10}+\frac{3}{10}\right\rbrack\cdot\frac54=\frac45\cdot\frac54=1\)
\(2)\left\lbrack\left(\frac56-\frac13\right):\left(\frac12+\frac14\right)\right\rbrack\cdot\frac25=\left\lbrack\left(\frac56-\frac26\right):\left(\frac24+\frac14\right)\right\rbrack\cdot\frac25\)
\(=\left\lbrack\frac12:\frac34\right\rbrack\cdot\frac25=\left(\frac12\cdot\frac25\right)\cdot\frac43=\frac15\cdot\frac43=\frac{4}{15}\)
bài 1:
\(1)\frac35\cdot\frac{7}{12}-\frac25=\frac{7}{20}-\frac{8}{20}=-\frac{1}{20}\)
\(2)\frac35-\left(-\frac47\right)\cdot\left(-\frac14\right)=\frac35-\frac17=\frac{21}{35}-\frac{5}{35}=\frac{16}{35}\)
\(3)-\frac45+18\cdot\left(-\frac13\right)^2=-\frac45+18\cdot\frac19=-\frac45+\frac{10}{5}=\frac65\)
\(4)\frac{-3}{2}+\frac{-14}{5}\cdot\frac{10}{7}=-\frac32+\frac{-8}{2}=-\frac{11}{2}\)
\(5)\left(\right.\frac{-1}{5})^2+9\cdot\left(-\frac23\right)^2=\frac{1}{25}+9\cdot\frac49=\frac{1}{25}+\frac{100}{25}=\frac{101}{25}\)
\(6)\left(\frac15\right)^2+\left(1-\frac32\right)^2:1\frac13-\frac56=\frac{1}{25}+\frac14\cdot\frac34-\frac56\)
\(=\frac{1}{25}+\frac{3}{16}-\frac56=\frac{48}{1200}+\frac{225}{1200}-\frac{1000}{1200}=-\frac{727}{1200}\)
bài 2:
\(1)\left(\frac49+\frac37\right)-\left(\frac37-\frac59\right)=\frac49+\frac37-\frac37+\frac59\)
\(=\left(\frac49+\frac59\right)+\left(\frac37-\frac37\right)=1+0=1\)
\(2)-\left(\frac{55}{27}-\frac{21}{5}\right)+\left(\frac{55}{27}-\frac{-4}{5}\right)=-\frac{55}{27}+\frac{21}{5}+\frac{55}{27}+\frac45\)
\(=\left(\frac{55}{27}-\frac{55}{27}\right)+\left(\frac{21}{5}+\frac45\right)=0+5=5\)
\(3)\frac37\cdot\frac58+\frac37\cdot\frac{11}{8}=\frac37\cdot\left(\frac58+\frac{11}{8}\right)=\frac37\cdot\frac{16}{8}=\frac37\cdot2=\frac67\)
\(4)\frac38\cdot20\frac34+\frac38\cdot19\frac14=\frac38\cdot\frac{83}{4}+\frac38\cdot\frac{77}{4}\)
\(=\frac38\cdot\left(\frac{83}{4}+\frac{77}{4}\right)=\frac38\cdot\frac{160}{4}=\frac38\cdot40=3\cdot5=15\)
bài 3:
\(1)\left\lbrack\left(\frac12+\frac13\right)\cdot\frac35+\frac{3}{10}\right\rbrack:\frac45=\left\lbrack\left(\frac36+\frac26\right)\cdot\frac35+\frac{3}{10}\right\rbrack\cdot\frac54\)
\(=\left\lbrack\frac56\cdot\frac35+\frac{3}{10}\right\rbrack\cdot\frac54=\left\lbrack\frac{5}{10}+\frac{3}{10}\right\rbrack\cdot\frac54=\frac45\cdot\frac54=1\)
\(2)\left\lbrack\left(\frac56-\frac13\right):\left(\frac12+\frac14\right)\right\rbrack\cdot\frac25=\left\lbrack\left(\frac56-\frac26\right):\left(\frac24+\frac14\right)\right\rbrack\cdot\frac25\)
\(=\left\lbrack\frac12:\frac34\right\rbrack\cdot\frac25=\left(\frac12\cdot\frac25\right)\cdot\frac43=\frac15\cdot\frac43=\frac{4}{15}\)
bài 1:
\(1)\frac35\cdot\frac{7}{12}-\frac25=\frac{7}{20}-\frac{8}{20}=-\frac{1}{20}\)
\(2)\frac35-\left(-\frac47\right)\cdot\left(-\frac14\right)=\frac35-\frac17=\frac{21}{35}-\frac{5}{35}=\frac{16}{35}\)
\(3)-\frac45+18\cdot\left(-\frac13\right)^2=-\frac45+18\cdot\frac19=-\frac45+\frac{10}{5}=\frac65\)
\(4)\frac{-3}{2}+\frac{-14}{5}\cdot\frac{10}{7}=-\frac32+\frac{-8}{2}=-\frac{11}{2}\)
\(5)\left(\right.\frac{-1}{5})^2+9\cdot\left(-\frac23\right)^2=\frac{1}{25}+9\cdot\frac49=\frac{1}{25}+\frac{100}{25}=\frac{101}{25}\)
\(6)\left(\frac15\right)^2+\left(1-\frac32\right)^2:1\frac13-\frac56=\frac{1}{25}+\frac14\cdot\frac34-\frac56\)
\(=\frac{1}{25}+\frac{3}{16}-\frac56=\frac{48}{1200}+\frac{225}{1200}-\frac{1000}{1200}=-\frac{727}{1200}\)
bài 2:
\(1)\left(\frac49+\frac37\right)-\left(\frac37-\frac59\right)=\frac49+\frac37-\frac37+\frac59\)
\(=\left(\frac49+\frac59\right)+\left(\frac37-\frac37\right)=1+0=1\)
\(2)-\left(\frac{55}{27}-\frac{21}{5}\right)+\left(\frac{55}{27}-\frac{-4}{5}\right)=-\frac{55}{27}+\frac{21}{5}+\frac{55}{27}+\frac45\)
\(=\left(\frac{55}{27}-\frac{55}{27}\right)+\left(\frac{21}{5}+\frac45\right)=0+5=5\)
\(3)\frac37\cdot\frac58+\frac37\cdot\frac{11}{8}=\frac37\cdot\left(\frac58+\frac{11}{8}\right)=\frac37\cdot\frac{16}{8}=\frac37\cdot2=\frac67\)
\(4)\frac38\cdot20\frac34+\frac38\cdot19\frac14=\frac38\cdot\frac{83}{4}+\frac38\cdot\frac{77}{4}\)
\(=\frac38\cdot\left(\frac{83}{4}+\frac{77}{4}\right)=\frac38\cdot\frac{160}{4}=\frac38\cdot40=3\cdot5=15\)
bài 3:
\(1)\left\lbrack\left(\frac12+\frac13\right)\cdot\frac35+\frac{3}{10}\right\rbrack:\frac45=\left\lbrack\left(\frac36+\frac26\right)\cdot\frac35+\frac{3}{10}\right\rbrack\cdot\frac54\)
\(=\left\lbrack\frac56\cdot\frac35+\frac{3}{10}\right\rbrack\cdot\frac54=\left\lbrack\frac{5}{10}+\frac{3}{10}\right\rbrack\cdot\frac54=\frac45\cdot\frac54=1\)
\(2)\left\lbrack\left(\frac56-\frac13\right):\left(\frac12+\frac14\right)\right\rbrack\cdot\frac25=\left\lbrack\left(\frac56-\frac26\right):\left(\frac24+\frac14\right)\right\rbrack\cdot\frac25\)
\(=\left\lbrack\frac12:\frac34\right\rbrack\cdot\frac25=\left(\frac12\cdot\frac25\right)\cdot\frac43=\frac15\cdot\frac43=\frac{4}{15}\)
giải gấp giúp mình vs, mình cảm ơn
