Các câu hỏi tương tự
Tính nhanh :
A = \(\left(\frac{2}{3}+\frac{3}{4}+....+\frac{99}{100}\right)\cdot\left(\frac{1}{2}+\frac{2}{3}+\frac{3}{4}+....+\frac{98}{99}\right)-\left(\frac{1}{2}+\frac{2}{3}+...+\frac{99}{100}\right)\cdot\left(\frac{2}{3}+\frac{3}{4}+...+\frac{98}{99}\right)\)
Bài 1: Tính nhanha) frac{2}{3.5}+frac{2}{5.7}+frac{2}{7.9}+...+frac{2}{19.21}b) left(1+frac{1}{2}right).left(1+frac{1}{3}right).left(1+frac{1}{4}right).....left(1+frac{1}{99}right)c) frac{frac{1}{2}+frac{1}{3}+frac{1}{4}+...+frac{1}{100}}{frac{1}{99}+frac{2}{98}+frac{3}{97}+...+frac{98}{2}+frac{99}{1}}Bài 2. Tìm x, biết:a) frac{x-2}{20}frac{5}{2-x}b) left(frac{x}{3}+frac{1}{2}right)left(75%-1frac{1}{2}xright)0Mk cảm ơn nhé. Các bn làm đc câu nào thì làm (nhất là b2)
Đọc tiếp
Bài 1: Tính nhanh
a) \(\frac{2}{3.5}\)+\(\frac{2}{5.7}\)+\(\frac{2}{7.9}\)+...+\(\frac{2}{19.21}\)
b) \(\left(1+\frac{1}{2}\right).\left(1+\frac{1}{3}\right).\left(1+\frac{1}{4}\right).....\left(1+\frac{1}{99}\right)\)
c) \(\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{100}}{\frac{1}{99}+\frac{2}{98}+\frac{3}{97}+...+\frac{98}{2}+\frac{99}{1}}\)
Bài 2. Tìm x, biết:
a) \(\frac{x-2}{20}=\frac{5}{2-x}\)
b) \(\left(\frac{x}{3}+\frac{1}{2}\right)\left(75\%-1\frac{1}{2}x\right)=0\)
Mk cảm ơn nhé. Các bn làm đc câu nào thì làm (nhất là b2)
Cho M = \(\frac{\left(\frac{1}{99}+\frac{2}{98}+\frac{3}{97}+...+\frac{99}{1}\right)}{\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+.....+\frac{1}{100}\right)}\);
N = \(\frac{\left(92-\frac{1}{9}-\frac{2}{10}-\frac{3}{11}-...-\frac{92}{100}\right)}{\left(\frac{1}{45}+\frac{1}{50}+\frac{1}{55}+....+\frac{1}{500}\right)}\)
Tìm tỉ số phần trăm của M và N
Afrac{1+frac{1}{3}+frac{1}{5}+frac{1}{7}+......+frac{1}{999}}{frac{1}{1.999}+frac{1}{3.997}+frac{1}{5.995}+......+frac{1}{999.1}}Bfrac{1+left(1+2right)+left(1+2+3right)+left(1+2+3+4right)+......+left(1+2+3+...+98right)}{1.2+2.3+3.4+4.5+......+98.99}Cfrac{frac{1}{1.300}+frac{1}{2.301}+frac{1}{3.302}+......+frac{1}{100.400}}{frac{1}{1.102}+frac{1}{2.103}+frac{1}{3.104}+......+frac{1}{299.400}}Dfrac{frac{1}{99}+frac{2}{98}+frac{3}{97}+......+frac{99}{1}}{frac{1}{2}+frac{1}{3}+frac{1}{4}+......+frac...
Đọc tiếp
\(A=\frac{1+\frac{1}{3}+\frac{1}{5}+\frac{1}{7}+......+\frac{1}{999}}{\frac{1}{1.999}+\frac{1}{3.997}+\frac{1}{5.995}+......+\frac{1}{999.1}}\)
\(B=\frac{1+\left(1+2\right)+\left(1+2+3\right)+\left(1+2+3+4\right)+......+\left(1+2+3+...+98\right)}{1.2+2.3+3.4+4.5+......+98.99}\)
\(C=\frac{\frac{1}{1.300}+\frac{1}{2.301}+\frac{1}{3.302}+......+\frac{1}{100.400}}{\frac{1}{1.102}+\frac{1}{2.103}+\frac{1}{3.104}+......+\frac{1}{299.400}}\)
\(D=\frac{\frac{1}{99}+\frac{2}{98}+\frac{3}{97}+......+\frac{99}{1}}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+......+\frac{1}{100}}:\frac{92-\frac{1}{9}-\frac{2}{10}-\frac{3}{97}-......-\frac{92}{100}}{\frac{1}{45}+\frac{1}{50}+\frac{1}{55}+......+\frac{1}{500}}\)
\(H=\left(\frac{1}{2^2}-1\right)\left(\frac{1}{3^2}-1\right)...\left(\frac{1}{98^2}-1\right)\left(\frac{1}{99^2}-1\right)\)
\(A=\left(\frac{1}{2^2}-1\right)\left(\frac{1}{3^2}-1\right)\left(\frac{1}{4^2}-1\right)....\left(\frac{1}{98^2}-1\right)\left(\frac{1}{99^2}-1\right)\)
Tính:
\(A=\left(\frac{1}{2^2}-1\right)\left(\frac{1}{3^2}-1\right)\left(\frac{1}{4^2}-1\right)...\left(\frac{1}{98^2}-1\right)\left(\frac{1}{99^2}-1\right)\)
16 tháng 2 2020 lúc 10:02
Tính : \(K=\left(\frac{1}{3}+\frac{1}{3^2}+\frac{1}{3^3}+\frac{1}{3^4}\right).3^5+\left(\frac{1}{3^5}+\frac{1}{3^6}+\frac{1}{3^7}+\frac{1}{3^8}.3^9\right)+...+\left(\frac{1}{3^{97}}+\frac{1}{3^{98}}+\frac{1}{3^{99}}+\frac{1}{3^{100}}\right).3^{101}\)
\(B=\left(\frac{1}{2}-1\right):\left(\frac{1}{3}-1\right):\left(\frac{1}{4}-1\right):...:\left(\frac{1}{98}-1\right):\left(\frac{1}{99}-1\right):\left(\frac{1}{100}-1\right)\)