Các câu hỏi tương tự
Cho C=\(\left(1-\frac{1}{2^2}\right)\left(1-\frac{1}{3^2}\right)\left(1-\frac{1}{4^2}\right).........\left(1-\frac{1}{100^2}\right)\)
Chung to bieu thuc C.200 la mot so nguyen
cmr
B=\(\left(1-\frac{3}{2.4}\right)\left(1-\frac{3}{3.5}\right)\left(1-\frac{3}{4.6}\right)...\left(1-\frac{3}{n\left(n+2\right)}\right)< 2 \)Voi moi so nguyen duong n
cho a, b, c, d la 4 so nguyen duong thoa man: b= \(\frac{a+c}{2}va\frac{1}{c}=\frac{1}{2}.\left(\frac{1}{b}+\frac{1}{d}\right)\)
chung minh: \(\frac{a}{b}=\frac{c}{d}\)
Tap hop cac so nguyen x thoa man \(\frac{1}{2}-\left(\frac{1}{3}+\frac{3}{4}\right)
CMR :\(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+.....+\frac{1}{16}\)không phải là số nguyên
tim tat ca cac cap so nguyen x,y thoa man;\(\frac{1}{x}\)+\(\frac{1}{y}\)=\(\frac{1}{p}\)trong do p la so nguyen to cho truoc
\(\frac{\frac{1}{3}+\frac{1}{7}-\frac{1}{17}}{\frac{2}{3}+\frac{2}{7}-\frac{2}{17}}.\frac{\frac{3}{4}-\frac{3}{16}-\frac{3}{256}+\frac{3}{4}}{1-\frac{1}{4}+\frac{1}{16}-\frac{1}{64}}-\frac{-5}{8}\)
\(\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{\frac{2}{3}-\frac{2}{7}-\frac{2}{13}}\times\frac{\frac{3}{4}-\frac{2}{16}-\frac{3}{64}-\frac{3}{264}}{1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}}\)
tìm so nguyen x biet: a) \(\frac{1}{1x3}+\frac{1}{3x5}+\frac{1}{5x7}+..........+\frac{1}{\left(2x-1\right)x\left(2x+1\right)}=\frac{49}{99}\)
b) 1-3+32-33+.........+(-3)x=\(\frac{9^{1006}-1}{4}\)