3/4+3= 3/4+12/4=15/4

5/2 x 4 =5 x 4/2 = 20/2 = 10

2-7/8=16/8-7/8=9/8

9/4-2=9/4-8/4=1/4

5: 5/7=5 x 7/5= 35/5=7

5/6:2/7=5/6 x 7/2 = 35/12

1/6+2/3 x 8/9= 1/6+ 16/18= 3/18+16/18=19/18

1/6 + 2/3 : 4/5 = 1/6+ 2/3 x 5/4= 1/6+5/6=6/6=1

                đúng cho mình nhé

Ý bạn là như thế này

\(2^{15}.\frac{9^4}{6^3}.8^3=2^{15}\frac{3^8}{3^3.2^3}.2^9=2^{24}.3^5:2^3=2^{21}.3^5=509607936\)

Hay là thế này

\(\frac{2^{15}.9^4}{6^3.8^3}=\frac{2^{15}.3^8}{3^3.2^3.2^9}=\frac{2^{15}.3^8}{3^3.2^{11}}=2^4.3^5=3888\)

Cái nào trong số này là ý của bạn

Cách làm như bạn kia nhưng khi làm bạn ấy làm sai 9 + 3 = 11 ? Thế là kết quả phải ra 1944

41/54

41/54

\(\frac{2^{15}.9^4}{6^3.8^3}\)

\(=\frac{2^{15}.\left(3^2\right)^4}{\left(2.3\right)^3.\left(2^3\right)^3}\)

\(=\frac{2^{15}.3^8}{\left(2^3.2^9\right).3^3}\)

\(=\frac{2^{15}.3^8}{2^{12}.3^3}\)

\(=2^3.3^5=8.243=1944\)

Ta có: \(\frac{1}{1\times10}+\frac{1}{2\times9}+\cdots+\frac{1}{10\times1}\)

\(=2\times\left(\frac{1}{1\times10}+\frac{1}{2\times9}+\cdots+\frac{1}{5\times6}\right)\)

\(=\frac{2}{11}\times\left(\frac{11}{1\times10}+\frac{11}{2\times9}+\cdots+\frac{11}{5\times6}\right)\)

\(=\frac{2}{11}\times\left(1+\frac12+\frac13+\cdots+\frac19+\frac{1}{10}\right)\)

Ta có: \(A=\frac{1+\frac12+\cdots+\frac{1}{10}}{\frac{1}{1\times10}+\frac{1}{2\times9}+\cdots+\frac{1}{9\times2}+\frac{1}{10\times1}}\)

\(=\frac{1+\frac12+\cdots+\frac{1}{10}}{\frac{2}{11}\times\left(1+\frac12+\cdots+\frac{1}{10}\right)}=1:\frac{2}{11}=\frac{11}{2}\)

Ta có: \(\frac{1}{1\times10}+\frac{1}{2\times9}+\cdots+\frac{1}{10\times1}\)

\(=2\times\left(\frac{1}{1\times10}+\frac{1}{2\times9}+\cdots+\frac{1}{5\times6}\right)\)

\(=\frac{2}{11}\times\left(\frac{11}{1\times10}+\frac{11}{2\times9}+\cdots+\frac{11}{5\times6}\right)\)

\(=\frac{2}{11}\times\left(1+\frac12+\frac13+\cdots+\frac19+\frac{1}{10}\right)\)

Ta có: \(A=\frac{1+\frac12+\cdots+\frac{1}{10}}{\frac{1}{1\times10}+\frac{1}{2\times9}+\cdots+\frac{1}{9\times2}+\frac{1}{10\times1}}\)

\(=\frac{1+\frac12+\cdots+\frac{1}{10}}{\frac{2}{11}\times\left(1+\frac12+\cdots+\frac{1}{10}\right)}=1:\frac{2}{11}=\frac{11}{2}\)

helpppppp meeeeeeee

=2/7x3/2x8-4/5

=24/7-4/5

=120/35-28/35=92/35

\(\dfrac{2}{7}:\dfrac{2}{3}\times8-\dfrac{4}{5}=\dfrac{2}{7}\times\dfrac{3}{2}\times8-\dfrac{4}{5}=\dfrac{24}{7}-\dfrac{4}{5}=\dfrac{120}{35}-\dfrac{28}{35}=\dfrac{92}{35}\)

\(\dfrac{1.4+2.6+3.8+4.10+5.12}{5.2+10.3+15.4+20.5+25.6}\)

\(=\dfrac{2\left(1.2+2.3+3.4+4.5+5.6\right)}{5\left(1.2+2.3+3.4+4.5+5.6\right)}\)

\(=\dfrac{2}{5}\)