Rút gọn phân số: 

\(\frac{24-12.13}{12+4.9}=\frac{24-4.3.13}{12+4.9}=\frac{24-3.13}{12+9}=\frac{24-3.13}{12+3.3}=\frac{24-13}{12+3}=\frac{11}{14}\)

Sai thì thôi nhé!

\(\frac{24-12.13}{12+4.9}\)=\(\frac{24-156}{12+36}\)=\(\frac{-132}{48}\)=-\(\frac{11}{4}\)

Mình nhầm, đoạn cuối \(=\frac{11}{15}\), bạn sửa lại cho mình nhé!

Have a nice day!

a) \(\dfrac{11\cdot8-11\cdot3}{17-6}\)

\(=\dfrac{11\cdot\left(8-3\right)}{11}=5\)

b) \(\dfrac{24-12\cdot13}{12+4\cdot9}\)

\(=\dfrac{12\cdot\left(2-13\right)}{12\left(1+3\right)}=\dfrac{-11}{4}\)

\(\frac{24-12.13}{12+4.9}=\frac{12.2-12.13}{4.3+4.9}\frac{12.\left(2-13\right)}{4.\left(3+9\right)}=\frac{3.\left(-11\right)}{12}=\frac{-11}{4}\)

đây nhé

\(\frac{2^{19}.27^3+15.4^4.9^4}{6^9.2^{10}+12^{10}}=\frac{2^{19}.3^9+5.2^8.3^9}{2^9.3^9+2^{20}.3^{10}}=\frac{2^8.3^9\left(2^{11}-5\right)}{2^9.3^9\left(1+2^{11}.3\right)}=\frac{2043}{2.6145}=\frac{2043}{12290}\)

\(\frac{2^{19}\cdot27^3+15\cdot4^4\cdot9^4}{6^9\cdot2^{10}+12^{10}}\)

\(=\frac{2^{19}\cdot3^9+3\cdot5\cdot2^8\cdot3^8}{2^9\cdot3^9+2^{20}\cdot3^{10}}\)

\(=\frac{2^8\cdot3^9\left(2^{11}+5\right)}{2^9\cdot3^9\left(2^{11}\cdot3+1\right)}\)

\(=\frac{\left(2^{11}+5\right)}{2\left(2^{11}\cdot3+1\right)}\)

???

a)  5

b)  − 11 4

 Ta có: \(\frac{{12}}{{ - 24}} = \frac{{12:12}}{{ - 24:12}} = \frac{1}{{ - 2}}\)

\(\frac{{ - 39}}{{75}} = \frac{{ - 39:3}}{{75:3}} = \frac{{ - 13}}{{25}}\)

\(\frac{{132}}{{ - 264}} = \frac{{132:132}}{{ - 264:132}} = \frac{1}{{ - 2}}\).