dễ thế mà

chỉ là tính thôi có j đâu

\(\left(\frac{-3}{4}+\frac{2}{5}\right):\frac{3}{7}+\left(\frac{3}{5}+\frac{-1}{4}\right):\frac{3}{7}\)

\(=\left(\frac{-3}{4}+\frac{2}{5}+\frac{3}{5}+\frac{-1}{4}\right):\frac{3}{7}\)

\(=\left[\left(\frac{-3}{4}+\frac{-1}{4}\right)+\left(\frac{2}{5}+\frac{3}{5}\right)\right]:\frac{3}{7}\)

\(=\left(-1+1\right):\frac{3}{7}\)

\(=0:\frac{3}{7}\)

\(=0\)

Học tốt

Mọi người đánh giúp mình nhé! Hạn là tối nay!!

a, \(\frac{2}{5}.\frac{1}{3}-\frac{2}{15}:\frac{1}{5}+\frac{3}{5}.\frac{1}{3}\)

\(=\frac{1}{3}.\left(\frac{2}{5}+\frac{3}{5}\right)-\frac{2}{15}.5\)

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

\(=\frac{1}{3}-\frac{2}{3}\)

\(=\frac{-1}{3}\)

b, \(\left(6-2\frac{4}{5}\right).3\frac{1}{8}+1\frac{3}{8}:\frac{1}{4}\)

\(=\left(6-\frac{14}{5}\right).\frac{25}{8}+\frac{11}{8}.4\)

\(=\frac{16}{5}.\frac{25}{8}+\frac{11}{2}\)

\(=10+\frac{11}{2}\)

\(=\frac{31}{2}\)

1/3×(3/5+2/5)-2/15×1/5

1/3×1-2/15×1/5

1/3-2/15×1/5

1/3-2/75

25/75-2/75

23/75

(6-14/5)×25/8-11/8:4/1

16/5×25/8-11/8:4/1

10/1-11/8:4/1

10/1-11/8×1/4

10/1-11/32

320/32-11/32

309/32

a) A = \(\frac{15}{7}:\left(\frac{1}{15}-\frac{7}{5}\right)-\frac{15}{7}:\left(\frac{17}{15}+\frac{11}{5}\right)=\frac{15}{7}:\frac{-20}{15}-\frac{15}{7}:\frac{50}{15}\)

A = \(\frac{15}{7}.\frac{15}{-20}-\frac{15}{7}.\frac{15}{50}=\frac{15}{7}.\left(\frac{-15}{20}-\frac{15}{50}\right)=\frac{15}{7}.\frac{-105}{100}=-\frac{9}{4}\)

b) B = \(\frac{1}{\left(-\frac{2}{3}\right)^4}.\left(-4\right)^2-1^{2016}-10\frac{1}{3}=\frac{1}{\frac{16}{81}}.16-1-10\frac{1}{3}=\frac{81}{16}.16-1-10\frac{1}{3}\)

B = \(81-1-10-\frac{1}{3}=70-\frac{1}{3}=\frac{209}{3}\)

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

bai de the ma cung hoi

a) \(\left|-\frac{6}{7}\right|\div\left(-2\right)^3-\sqrt{\frac{9}{16}}\)

\(=\frac{6}{7}\div\left(-8\right)-\frac{3}{4}\)

\(=\frac{-3}{28}-\frac{3}{4}\)

\(=\frac{-6}{7}\)

b) \(-5\frac{5}{9}\div\left(-1\frac{3}{4}\right)+4\frac{5}{9}\div\left(-1\frac{3}{4}\right)\)

\(=\left(-5\frac{5}{9}+4\frac{5}{9}\right)\div\left(-1\frac{3}{4}\right)\)

\(=\left(-5+\frac{5}{9}+4+\frac{5}{9}\right)\div\frac{-7}{4}\)

\(=\left(-1+\frac{10}{9}\right).\frac{-4}{7}\)

\(=\frac{1}{9}.\frac{-4}{7}\)

\(=\frac{-4}{63}\)

c) \(-63,99-\left(\frac{4}{9}-63,99\right)-\left(-1\frac{2}{3}\right)^2\)

\(=-63,99-\frac{4}{9}+63,99-\left(\frac{-5}{3}\right)^2\)

\(=-63,99-\frac{4}{9}+63,99-\frac{25}{9}\)

\(=\left(-63,99+63,99\right)-\left(\frac{4}{9}+\frac{25}{9}\right)\)

\(=-\frac{29}{9}\)