âm 2( số -2) và 4/25

\(\frac{-3}{31}+\frac{-6}{17}+\frac{1}{25}+\frac{-28}{31}+\frac{-11}{17}+\frac{-1}{5}\)

\(=\left(\frac{-3}{31}+\frac{-28}{31}\right)+\left(\frac{-6}{17}+\frac{-11}{17}\right)+\left(\frac{1}{25}+\frac{-1}{5}\right)\)

\(=\frac{-31}{31}+\frac{-17}{17}+\frac{-4}{25}\)

\(=\left(-1\right)+\left(-1\right)+\frac{-4}{25}\)

\(=\frac{\left(-25\right)+\left(-25\right)+\left(-4\right)}{25}\)

\(=\frac{-54}{25}\)

a)(1/4+3/4)-(5/13+8/13)+2/11=1-1+2/11=2/11

b)(21/31+10/31)-16/7+(44/53+9/53)=1+1-16/7=14/7-16/7=-2/7

bằng2/11

         -16/7

Trả lời

b)(1/3+12/67+13/41)-(79/67-28/41)

=1/3+12/67+13/41-79/67+28/41

=1/3+(12/67-79/67)+(13/41+28/41)

=1/3+(-67/67)+41/41

=1/3+(-1)+1

=1/3+0

=1/3.

c)38/45-(8/45-17/51-3/11)

=38/45-8/45+17/51+3/11

=30/45+1/3+3/11

=2/3+1/3+3/11

=3/3+3/11

=1+3/11

=1 3/11.

\(\frac{\frac{1}{9}-\frac{5}{6}-4}{\frac{7}{12}-\frac{1}{36}-10}=\frac{36.\left(\frac{1}{9}-\frac{5}{6}-4\right)}{36.\left(\frac{7}{12}-\frac{1}{36}-10\right)}\)

                             \(=\frac{4-6.5-36.4}{3.7-1-36.10}\)

                               \(=\frac{4-30-144}{21-1-360}\)

                               \(=\frac{-26-144}{20-360}=\frac{-170}{-340}=\frac{1}{2}\)

\(\frac{\frac{4}{36}-\frac{30}{36}-\frac{144}{36}}{\frac{21}{36}-\frac{1}{36}-\frac{360}{36}}=\frac{\frac{-170}{36}}{\frac{-340}{36}}=\frac{-170}{36}:\frac{-340}{36}=\frac{-170}{36}.\frac{36}{-340}=\frac{-170}{-340}=\frac{1}{2}\)

\(a)\frac{1}{3}+\frac{-2}{5}+\frac{1}{6}+\frac{-1}{5}\le x< \frac{-3}{4}+\frac{2}{7}+\frac{-1}{4}+\frac{3}{5}+\frac{5}{7}\)

\(\Rightarrow\frac{1}{3}+\frac{1}{6}+\frac{-2}{5}+\frac{-1}{5}\le x< \frac{-3}{4}+\frac{-1}{4}+\frac{2}{7}+\frac{5}{7}+\frac{3}{5}\)

\(\Rightarrow\frac{2}{6}+\frac{1}{6}+\frac{-3}{5}\le x< -1+1+\frac{3}{5}\)

\(\Rightarrow\frac{1}{2}+\frac{-3}{5}\le x< \frac{3}{5}\)

\(\Rightarrow\frac{-1}{10}\le x< \frac{6}{10}\)

\(\Rightarrow-1\le x< 6\)

\(\Rightarrow x\in\left\{-1;0;1;2;3;4;5\right\}\)

Bài b tương tự

bạn ơi bạn giải câu b được ko. mk ko biết làm câu b

\(\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times\left(\frac{-5}{12}+\frac{1}{4}+\frac{1}{6}\right)\)

\(=\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times\left(\frac{-5}{12}+\frac{3}{12}+\frac{2}{12}\right)\)

\(=\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times\left(\frac{-5+3+2}{12}\right)\)

\(=\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times0\)

\(=0\)

_Chúc bạn học tốt_

\(\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times\left(\frac{-5}{12}+\frac{1}{4}+\frac{1}{6}\right)\)

\(=\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times\left(\frac{-5}{12}+\frac{3}{12}+\frac{2}{12}\right)\)

\(=\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times\left(\frac{-5+3+2}{12}\right)\)

\(=\left(\frac{17}{28}+\frac{18}{29}-\frac{19}{30}-\frac{30}{31}\right)\times0\)

\(=0\)

_Chúc bạn học tốt_

\(x = {-b \pm \sqrt{b^2-4ac} \over 2a} đây là biểu thức gì\)