\(\dfrac{3}{4}.\dfrac{2}{3}-\dfrac{1}{6}.\dfrac{3}{4}-\dfrac{3}{4}.\dfrac{1}{2}\) 

= \(\dfrac{3}{4}.\left(\dfrac{2}{3}-\dfrac{1}{6}-\dfrac{1}{2}\right)\) 

= \(\dfrac{3}{4}.0\) 

= 0

\(\dfrac{3}{4}\cdot\dfrac{2}{3}-\dfrac{1}{6}\cdot\dfrac{3}{4}-\dfrac{3}{4}\cdot\dfrac{1}{2}\)

\(=\dfrac{3}{4}\left(\dfrac{2}{3}-\dfrac{1}{6}-\dfrac{1}{2}\right)\)

\(=\dfrac{3}{4}\cdot\left(\dfrac{4}{6}-\dfrac{1}{6}-\dfrac{3}{6}\right)\)

=0

\(\frac{4}{5}\cdot\frac{3}{7}+\frac{4}{5}\cdot\frac{6}{7}-\frac{4}{5}\cdot\frac{4}{14}\)

\(=\frac{4}{5}\cdot\left(\frac{3}{7}+\frac{6}{7}-\frac{4}{14}\right)\)

\(=\frac{4}{5}\cdot1=\frac{4}{5}\)

                                                                     #Louis

a 15/7"3/4

\(\frac{3}{4}x\frac{5}{6}-\frac{1}{6}=\frac{11}{24}\)

\(4\frac{8}{5}-\frac{2}{3}=\frac{28}{5}-\frac{2}{3}=\frac{74}{15}\)

bn viết p/s hoặc dùng / cho dễ

dễ, nhưng phai giai dc câu nay  60% nhan x cong 2 phan 3 = 1 phan 3 nhan 6va 1 phan 3

dễ mà

1.a) 3/4*2/9+1/3=1/2

  b)1/4:1/3-1/2=1/4

\(a,\frac{1}{2}\)

\(b,\frac{1}{4}\)

a,1/2

b,1/4

j cai

b2 giải

a, 36 x 45 / 6 x5 = 6 x 6 x 9 x 5 / 6 x 5 = 54.

b, 56 x 63 / 9 x 8 = 8 x 7 x 7 x9 / 9 x 8 = 49. 

Vậy..........

\(\frac{4}{3}\pi\left(696000000\right)^3=\frac{x.4}{5}\pi\left(6371000\right)^3\)

\(\Rightarrow x\approx2172969,6\)