Đang cần gấp ạ.
Ta có :
1/2x6 + 1/4x9 + 1/6x12 +...+1/198 x 300
= 1/6x2 + 1/6x6 + 1/6x12 + ....+1/6x9900
= 1/6 x ( 1/2 + 1/6 + 1/ 12 +...+1/9900)
= 1/6 x (1/1x2 + 1/2x3 + 1/3x4+...+1/99x100)
=1/6x (1-1/2 + 1/2-1/3 + 1/3 - 1/4 + ....+1/99-1/100)
=1/6x(1-1/100)
=1/6 x 99/100
= 33/200
k cho mình nha , học tốt
\(\frac{1}{3\times4}-\frac{1}{4\times5}-\frac{1}{5\times6}-\frac{1}{6\times7}-\frac{1}{7\times8}-\frac{1}{8\times9}-\frac{1}{9\times10}\)
Các bạn ơi ,giúp mình với
Bài 1:Rút gọn
a)\(\frac{2^{19}\times27^3+15\times4^9\times9^4}{6^9\times2^{10}+12^{10}}\)
b)\(\frac{\left(\frac{-1}{2}\right)^3-\left(\frac{3}{4}\right)^3\times\left(-2\right)^2}{2\times\left(-1\right)^5+\left(\frac{3}{4}\right)^2-\frac{3}{8}}\)
c)\(\frac{45\times9^4-2\times6^4}{2^{19}\times3^8+6^8\times20}\)
Bài 2:Tìm x
a)\(5^x+5^{x+2}=650\)
b)\(3^{x-1}+5\times3=162\)
Tính giá trị biểu thức:
a. \(\frac{20^5\times5^{10}}{100^5}\)
b. \(\frac{\left(0,9\right)^5}{\left(0,3\right)^6}\)
c. \(\frac{6^3+3\times6^2+3^3}{-13}\)
d. \(\frac{4^6\times9^5+6^9\times120}{8^4\times3^{12}-6^{11}}\)
e. \(\left(2^{-1}+3^{-1}\right):\left(2^{-1}-3^{-1}\right)+\left(2^{-1}\times2^0\right)\times2^3\)
f. \(\left(\frac{-1}{3}\right)^{-1}-\left(\frac{-3}{5}\right)^6+\left(\frac{1}{2}\right)^2:2\)
tính \(\frac{4^6\times9^5+120\times6^9}{8^4\times3^{12}-6^{11}}\)
Tính
\(\frac{\left(-0,25\right)^{-5}\times9^4\times\left(-2\right)^{-3}-2^{-2}\times6^9}{2^9\times3^6+6^6\times40}\)
Tính hợp lí
H = \(\frac{2\times8^4+27^2+4\times6^9}{2^7\times6^7+2^7\times40\times9^4}\)
TÍNH
\(\frac{\left(1+2+3+...+100\right)\times\left(\frac{1}{3}-\frac{1}{5}-\frac{1}{7}-\frac{1}{9}\right)\times\left(6,3\times12-21\times3,6\right)}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{100}}\)
Bài 1 : Tính :
a)\(\frac{\left(13\frac{1}{4}-2\frac{5}{27}-10\frac{5}{6}\right)\times230\frac{1}{5}+46\frac{3}{4}}{\left(1\frac{3}{10}+\frac{10}{3}\right)\div\left(12\frac{1}{3}-14\frac{2}{7}\right)}\)
b) \(\frac{2^{12}\times3^5-4^6\times9^2}{\left(2^4\times3\right)^6+8^4\times3^5}-\frac{5^{10}\times7^3-25^5\times49^2}{\left(125\times7\right)^3+5^9\times14^3}\)
c)P=\(\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+....+\frac{1}{2016}}{\frac{2015}{1}+\frac{2014}{2}+\frac{2013}{3}+....+\frac{1}{2015}}\)
Rút gọn
\(\frac{4^5\times9^4-2\times6^9}{2^{10}\times3^8+6^8\times20}\)
