\(\frac{7}{18}.\frac{8}{11}-\frac{7}{9}.\frac{8}{11}-11:\frac{9}{2}\)

\(=\frac{8}{11}.\left(\frac{7}{18}-\frac{7}{9}\right)-11:\frac{9}{2}\)

\(=\frac{8}{11}.\left(-\frac{7}{18}\right)-11:\frac{9}{2}\)

\(=-\frac{28}{99}-\frac{22}{9}\)

\(=-\frac{30}{11}\)

Tk mk nha!!!!!!

\(\left|2x-1\right|^5=\left|1-2x\right|^3\)

\(\left|2x-1\right|^5=\left|2x-1\right|^3\)

\(\left|2x-1\right|^3\cdot\left|2x-1\right|^2-\left|2x-1\right|^3=0\)

\(\left|2x-1\right|^3\cdot\left(\left|2x-1\right|^3-1\right)=0\)

\(\Rightarrow\orbr{\begin{cases}2x-1=0\\\left|2x-1\right|^3=1\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}2x=1\\2x-1=1\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=\frac{1}{2}\\x=1\end{cases}}\)

Vậy,.........

\(\frac{25}{36}.\frac{-8}{11}+\frac{5}{18}.\frac{14}{11}.\frac{-5}{2}\)

\(=\frac{25}{36}.\frac{-8}{11}+\frac{14}{11}.\frac{-25}{36}\)

\(=\frac{-25}{36}\left(\frac{8}{11}+\frac{14}{11}\right)\)

\(=\frac{-25}{36}.\frac{32}{11}\)

\(=\frac{-200}{99}.\)

tk nha

Đề bài :Tìm x\(\in\)Z,để các phân số sau tối giản

trả lời đúng mình sẽ kết bn

\(\frac{a}{b}=\frac{c}{d}\Rightarrow\frac{a}{c}=\frac{b}{d}\)

Áp dụng tính chất của dãy tỉ số bằng nhau ta có :

\(\frac{a}{c}=\frac{b}{d}=\frac{4a+2b}{4a+2d}\left(1\right)\)

\(\frac{a}{c}=\frac{b}{d}=\frac{7a-5b}{7c-5d}\left(2\right)\)

Từ (1)(2) => đpcm

\(5-\frac{1}{2}-\frac{5}{6}-\frac{11}{12}-\frac{19}{20}-\frac{29}{30}\)

\(=\left(1-\frac{1}{2}\right)+\left(1-\frac{5}{6}\right)+\left(1-\frac{11}{12}\right)+\left(1-\frac{19}{20}\right)+\left(1-\frac{29}{30}\right)\)

\(=\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}\)

\(=\frac{1}{1\cdot2}+\frac{1}{2\cdot3}+\frac{1}{3\cdot4}+\frac{1}{4\cdot5}+\frac{1}{5\cdot6}\)

\(=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{5}-\frac{1}{6}\)

\(=1-\frac{1}{6}\)

\(=\frac{5}{6}\)

Đáp án : \(\frac{5}{6}\)

TK NHA!!