câu 1 . Thực hiện phép tính
a. 0,05 + 5 - \(\dfrac{1}{2}\)
b. \(\dfrac{6}{15}-\dfrac{7}{8}+3-\dfrac{3}{5}-\dfrac{2}{16}\)
c. \(\dfrac{3}{5}.\dfrac{15}{7}-\dfrac{15}{7}.\dfrac{8}{5}\)
d. \(\dfrac{2}{5.7}+\dfrac{2}{7.9}+\dfrac{2}{9.11}+....+\dfrac{2}{93.99}\)
e. \(\dfrac{7}{4}:\dfrac{-9}{8}-\dfrac{3}{9}\)
f. \(\dfrac{15}{17}.\dfrac{19}{21}+\dfrac{19}{21}.\dfrac{2}{17}+\dfrac{13}{21}\)
g. \(\left(4-\dfrac{5}{12}\right):2+\dfrac{5}{24}\)
Tính giá trị biểu thức:
a,\(A=\dfrac{3^6.45^4-15^{13}.5^{-9}}{27^4.25^3+45^6}\)
b,\(^{B=\dfrac{\left[\left(6,2:0,31-\dfrac{5}{6}.0,9\right).0,2+0,15\right]:12}{\left(2+1\dfrac{4}{11}.0,22:0,1\right).\dfrac{1}{33}}}\)
c,\(C=\dfrac{\left(\dfrac{3}{4}\right)^3+\left(\dfrac{5}{4}\right)^3-5\left(\dfrac{4}{3}-\dfrac{5}{4}\right)}{\left(\dfrac{-5}{8}\right)^2+\left(\dfrac{2}{3}\right)^2-\dfrac{5}{6}}\)
d,\(D=\left[\dfrac{\dfrac{17}{24}.9\dfrac{1}{2}-3\dfrac{1}{4}.\dfrac{17}{24}}{3\dfrac{1}{2}.2\dfrac{13}{36}+2\dfrac{13}{36}.2\dfrac{3}{4}}-\dfrac{1}{5}\right]^{-2}\)
Giúp em với chị @Nhã Doanh ới!!!!!!!!
Mai em phải đi thi rồi :((
1.thực hiện phép tính
a.\(\dfrac{-5}{21}-\dfrac{1}{3}+3\dfrac{1}{2}.\left(\dfrac{-2}{3}\right)^3\)
b)\(-2\dfrac{1}{3}+\left(\dfrac{3}{8}-\dfrac{3}{4^{^{ }}}\right)^3:\dfrac{5}{9}-\dfrac{1}{2}\)
c)\(\left(6-2\dfrac{4}{5}\right).3\dfrac{1}{8}-1\dfrac{3}{5}:\left(-\dfrac{1}{2}\right)^2\)
d)\(-\dfrac{3}{7}.\dfrac{5}{9}+\dfrac{4}{7}.\dfrac{-1}{3}-\left(0,5\right)^3\)
e)\(\dfrac{15}{5}-\dfrac{2}{17}+\dfrac{15}{23}-\dfrac{15}{17}+\dfrac{4}{19}\)
Giúp mik nha mai mik phải nộp bài cho thầy rùi nì
a,\(\dfrac{8^{20}+4^{20}}{4^{25}+64^5}\)
b,\(\left(1+\dfrac{2}{3}-\dfrac{1}{4}\right).\left(\dfrac{4}{5}-\dfrac{3}{4}\right)^2\)
c,\(23\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)-13\dfrac{1}{3}:\left(\dfrac{-5}{7}\right)\)
d,1:\(\left(\dfrac{2}{3}-\dfrac{3}{4}\right)^2\)
e,\(\dfrac{45^{10}.5^{20}}{75^{15}}\)
Tính nhanh nếu có thể
1. \(\dfrac{-1}{24}-[\dfrac{1}{4}-\left(\dfrac{1}{2}-\dfrac{7}{8}\right)]\)
2. \((\dfrac{5}{7}-\dfrac{7}{5})-[\dfrac{1}{2}-(-\dfrac{2}{7}-\dfrac{1}{10})]\)
3.\(\dfrac{1}{3\cdot5}+\dfrac{1}{5\cdot7}+\dfrac{1}{7\cdot9}+.......+\dfrac{1}{2015\cdot2017}\)
Tìm x:
a)\(-3\dfrac{x}{2}-1\dfrac{1}{2}=2\)
b)\(\dfrac{x+1}{2}=\dfrac{8}{x+1}\)
c)\(\dfrac{x-2}{27}+\dfrac{x-3}{26}+\dfrac{x-4}{25}+\dfrac{x-5}{24}+\dfrac{x-44}{5}=1\)
HELP ME!!!!!! Mk ko bít lm???
\(tính:\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}-\dfrac{1}{5}+\dfrac{1}{6}-\dfrac{1}{7}+\dfrac{1}{8}+\dfrac{1}{7}-\dfrac{1}{6}+\dfrac{1}{5}-\dfrac{1}{4}+\dfrac{1}{3}-\dfrac{1}{2}\)
A=\(\dfrac{\dfrac{3}{4}-\dfrac{3}{11}+\dfrac{3}{13}}{\dfrac{5}{7}-\dfrac{5}{11}+\dfrac{5}{13}}+\dfrac{\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}}{\dfrac{5}{4}-\dfrac{5}{6}+\dfrac{5}{8}}\)
giúp mình với
gấp gấp lắm
1/ tìm x
a) \(x.\left(x+\dfrac{2}{3}\right)=0\)
2/tìm giá trị nhỏ nhất của các biểu thức
a) \(\left|x+\dfrac{4}{6}\right|\)
b) \(\left|x-\dfrac{1}{3}\right|\)
3/ tính
a) \(\left(1+2+3+...90\right).\left(12.34-668\right):\left(\dfrac{1}{3}+\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{1}{6}\right)\)
b) \(\dfrac{\dfrac{3}{7}-\dfrac{3}{11}+\dfrac{3}{13}}{\dfrac{5}{7}-\dfrac{5}{11}+\dfrac{5}{13}}+\dfrac{\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{4}}{\dfrac{5}{4}-\dfrac{5}{6}+\dfrac{5}{8}}\)