\(\frac{13}{42}+\frac{-5}{18}-\frac{11}{21}-\frac{-4}{14}\)
=\(\frac{13}{42}+\frac{-5}{18}-\frac{11}{21}+\frac{4}{14}\)
\(=\left(\frac{13}{42}-\frac{11}{21}+\frac{4}{14}\right)+\frac{-5}{18}\)
\(=\left(\frac{13}{42}-\frac{22}{42}+\frac{12}{42}\right)+\frac{-5}{18}\)
\(=\frac{3}{42}+\frac{-5}{18}\)
\(=\frac{9}{126}+\frac{-35}{126}\)
\(=-\frac{26}{126}\)\(=-\frac{13}{63}\)
Bài 1: Tìm x
a. \(x-\frac{5}{12}-\frac{4}{9}=\frac{-13}{18}\)
b. \(2-\left(x+\frac{3}{7}\right)=\frac{9}{-21}\)
c. \(x-\frac{-3}{11}=\frac{6}{22}+\frac{1}{4}\)
d. \(\frac{13}{36}-\frac{5}{18}-x=\frac{-11}{9}\)
e. \(x-\frac{3}{7}:\frac{9}{14}=\frac{-17}{3}\)
f. \(\left(x-\frac{1}{2}\right):\frac{3}{11}=\frac{11}{4}\)
g. \(\left(2x+\frac{3}{8}\right).\frac{7}{4}=-\frac{21}{32}\)
h. \(x-\frac{x}{3}=\frac{3}{57}:\frac{12}{19}\)
Vì dài qua cho nên bài 2 mình để riêng nhé
\(\frac{12^2\cdot4^{16}}{11\cdot2^{13}\cdot4^{11}-16^9}+\frac{7\cdot9+14\cdot27+21\cdot36}{21\cdot27+42\cdot81+63\cdot108}\)
bài 1:thực hiện phép tính :
a)\(\frac{3}{7}+\frac{5}{13}+\frac{4}{13}\)
b)\(\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
c)\(\frac{2}{5}.\frac{1}{3}-\frac{2}{15}:\frac{1}{5}+\frac{3}{5}.\frac{1}{3}\)
d)\(\left(4-\frac{5}{12}\right):2+\frac{5}{24}\)
e)\(\frac{7}{19}.\frac{8}{11}+\frac{3}{11}.\frac{7}{19}+\frac{-1}{19}\)
f)\(\frac{9}{27}+\frac{8}{24}+\frac{18}{27}-\frac{-16}{24}+\frac{2}{3}\)
g)\(\frac{-5}{21}+\frac{-2}{21}+\frac{8}{24}\)
h)\(\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{4}{-9}+\frac{7}{15}\)
i)\(\frac{7}{25}.\frac{39}{-14}.\frac{50}{78}\)
m.n làm nhanh cho mình nhé, chiều mình phải nộp rồi! cảm ơn m.n!
\(\frac{11^4.6-11^5}{11^4-11^5}:\frac{9^8.3-9^9}{9^8.5+9^8.7}\)
\(\frac{3}{5}:\left(\frac{-1}{5}-\frac{1}{6}\right)+\frac{3}{5}:\left(\frac{-1}{3}-1\frac{1}{15}\right)\)
\(\left(\frac{1}{2}-\frac{13}{14}\right):\frac{5}{7}-\left(-\frac{2}{21}+\frac{1}{7}\right):\frac{5}{7}\)
\(\frac{4^5.9^4-2.6^9}{2^{10}.3^8+6^8.20}\)
\(21\frac{13}{15}.\frac{-11}{5}+13\frac{2}{15}:\frac{-5}{11}+\left(\frac{3}{4}\right)^2\)
\(\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{19}+\frac{1}{20}+\frac{1}{21}>\frac{5}{11}\)
BÀI ÔN SỐ HỌC
1. Thực hiện mỗi phép tính sau bằng 2 cách:
a)\(3\frac{4}{9}+5\frac{1}{6}\)
Ví dụ :
Cách 1: \(3\frac{4}{9}+5\frac{1}{6}=\frac{31}{9}+\frac{31}{6}=\frac{62}{18}+\frac{93}{18}=\frac{155}{18}=8\frac{11}{18}\)
Cách 2:\(3\frac{4}{9}+5\frac{1}{6}=3\frac{8}{18}+5\frac{3}{18}=8\frac{11}{18}\)
b)\(8\frac{1}{14}-6\frac{3}{7}\)
c)\(7-3\frac{6}{7}\)
2. Áp dụng tính chất phép tính & qui tắc dấu ngoặc để tính giá trị các biểu thức sau:
a)A =\(11\frac{3}{13}-\left(3\frac{4}{7}+6\frac{3}{13}\right)\)
b)B =\(\left(7\frac{4}{9}+3\frac{8}{13}\right)-5\frac{4}{3}\)
c)C =\(\frac{-2}{7}.\frac{5}{11}+\frac{-2}{7}.\frac{6}{11}+5\frac{4}{7}\)
d)D =\(0,7.1\frac{3}{5}.30.0,375.\frac{4}{7}\)
3.Tìm các số nghịch đảo của các số sau : \(\frac{4}{7};6\frac{3}{8};\frac{-3}{17};0.37\)
4.Tìm x, biết :
0,5-\(\frac{2}{3}x=\frac{5}{12}\)
Tính giá trị biểu thức
a,\(A=\frac{24\cdot47-23}{24+47-23}\cdot\frac{3+\frac{3}{7}-\frac{3}{11}+\frac{3}{1001}-\frac{3}{13}}{\frac{9}{1001}-\frac{9}{13}+\frac{9}{7}-\frac{9}{11}+9}\)
b,\(M=\frac{1+2+2^2+2^3+...+2^{2012}}{2^{2014}-2}\)
c,\(A=81\cdot\left[\frac{12-\frac{12}{7}-\frac{12}{289}-\frac{12}{85}}{4-\frac{4}{7}-\frac{4}{289}-\frac{4}{85}}:\frac{5+\frac{5}{13}+\frac{5}{169}+\frac{5}{91}}{6+\frac{6}{13}+\frac{6}{169}+\frac{6}{91}}\right]:\frac{158158158}{711711711}\)
d,\(A=\frac{5\cdot\left(2^2.3^2\right)^9\cdot\left(2^2\right)^6-2\cdot\left(2^2\cdot3\right)^{14}\cdot3^4}{5\cdot2^{28}\cdot3^{18}-7\cdot2^{29}\cdot3^{18}}\)
Thực hiện phép tính sau :
a)\(11\frac{3}{13}-\left(2\frac{4}{7}+5\frac{3}{13}\right)\)
b)\(\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{10}\)
c)\(\frac{42}{46}+\frac{250}{286}+\frac{-2121}{2323}+\frac{-125125}{143143}\)
(Giải chi tiết các bạn nhá ^_^!!!)
