\(\frac{3.17-9}{3.16+15}\)
=\(\frac{3.\left(16+1\right)-9}{3.16+15}\)
=\(\frac{3.16+3.1-9}{3.16+15}\)
=\(\frac{3.16+3-9}{3.16+15}\)
=\(\frac{3-9}{15}\)(vì đã triệt tiêu 3.16)
=\(\frac{-6}{15}\)=\(\frac{-2}{5}\)
Tìm x, biết:
a)\(\frac{2^{2x-3}}{4^{10}}=8^3.16^5\)
b)7.2 x =2 9+5.2 8
Tính:
\(\frac{1}{3.10}+\frac{1}{3.17}+\frac{1}{17.24}+...+\frac{1}{73.80}-\frac{1}{2.9}-\frac{1}{9.16}-\frac{1}{16.23}-\frac{1}{23.30}\)
`A=(63/9.18 + 21/14.17) : (14/9.13 + 14/14.18 + 14/3.17)`
-4,54+3.17-6,46+2
mik cần gấp
Tính :
a, \(\frac{15}{1.6}.\frac{15}{6.11}.\frac{15}{11.16}...\frac{15}{2011.2016}\)
b, \(\frac{4^5.9^4-2.6^9}{2^{10}.3^8+6^8.20}:\sqrt{\frac{25}{9}}\)
bài 1: tìm x thuộc Z ,biết :
\(\frac{11}{15}-\frac{9}{10}< x< \frac{11}{15}:\frac{9}{10}\)
Thực hiện phép tính : \(20\frac{15}{16}.16\frac{8}{9}-20\frac{15}{16}.12\frac{8}{9}\)
Tính hợp lí:
a) \(\frac{-8}{15}.\left(-30\right).\left(\frac{15}{-8}\right).\frac{9}{10}\)
b) \(2\frac{1}{18}.\frac{23}{24}.\frac{9}{37}.\frac{48}{-15}\)
c) A=\(\frac{-0,8+\frac{4}{7}+\frac{4}{9}}{0,3.\frac{3}{14}-\frac{3}{18}}+\frac{0,23-3,5+\frac{2}{7}}{0,69-10,5+\frac{6}{7}}\)
\(A=\frac{1}{3}-\frac{3}{4}-\left(-\frac{3}{5}\right)+\frac{1}{72}-\frac{2}{9}-\frac{1}{36}+\frac{1}{15}\)\(\frac{1}{15}\)
\(B=\frac{1}{5}-\frac{3}{7}+\frac{5}{9}-\frac{2}{11}+\frac{7}{13}-\frac{9}{16}-\frac{7}{13}+\frac{2}{11}-\frac{5}{9}+\frac{3}{7}-\frac{1}{5}\)
