Các câu hỏi tương tự
Rút gọn :
a/ \(A=\frac{\frac{1}{19}+\frac{2}{18}+\frac{3}{17}+...+\frac{19}{1}}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{20}}\)
b/ \(B=\frac{\left(1+\frac{2012}{1}\right)\left(1+\frac{2012}{2}\right)...\left(1+\frac{2012}{1000}\right)}{\left(1+\frac{1000}{1}\right)\left(1+\frac{1000}{2}\right)...\left(1+\frac{1000}{2012}\right)}\)
\(\frac{\left(1+\frac{2012}{1}\right)\left(1+\frac{2012}{2}\right).......\left(1+\frac{2012}{100}\right)}{\left(1+\frac{1000}{1}\right)\left(1+\frac{1000}{2}\right).....\left(1+\frac{1000}{2012}\right)}\)
tính
\(B=\left(\frac{1}{2^2}-1\right).\left(\frac{1}{3^2}-1\right)....\left(\frac{1}{2012^2}-1\right)\)
Tính P=\(\left(1-\frac{1}{1+2}\right)\cdot\left(1-\frac{1}{1+2+3}\right)\cdot\left(1-\frac{1}{1+2+3+4}\right)\cdot...\cdot\left(1-\frac{1}{1+2+3+...+2012}\right)\)
\(B=\left(1-\frac{1}{2}\right)\left(1-\frac{1}{3}\right)\left(1-\frac{1}{4}\right)....\left(1-\frac{1}{2012}\right)\)Tính giá trị biểu thức
tinh:
\(A=\left(1-\frac{1}{1+2}\right).\left(1-\frac{1}{1+2+3}\right)......\left(1-\frac{1}{1+2+3+....2012}\right)\)
Câu 1 Tính giá trị biểu thức:a) A 2+5+8+11+...+2012b) Bleft(1-frac{1}{2}right).left(1-frac{1}{3}right).left(1-frac{1}{4}right).....left(1-frac{1}{2011}right).left(1-frac{1}{2012}right)Câu 2a) Tìm x,y nguyên biết : 2x.(3y-2) + (3y-2) -55b) CMR:frac{1}{4^2}+frac{1}{6^2}+frac{1}{8^2}+...+frac{1}{left(2nright)^2} frac{1}{4}
Đọc tiếp
Câu 1 Tính giá trị biểu thức:
a) A= \(2+5+8+11+...+2012\)
b) B=\(\left(1-\frac{1}{2}\right).\left(1-\frac{1}{3}\right).\left(1-\frac{1}{4}\right).....\left(1-\frac{1}{2011}\right).\left(1-\frac{1}{2012}\right)\)
Câu 2
a) Tìm x,y nguyên biết : 2x.(3y-2) + (3y-2) = -55
b) CMR:
\(\frac{1}{4^2}+\frac{1}{6^2}+\frac{1}{8^2}+...+\frac{1}{\left(2n\right)^2}< \frac{1}{4}\)
\(\left(1-\frac{1}{2}\right).\left(1-\frac{1}{3}\right)......\left(1-\frac{1}{2012}\right)\)
Thực hiện phép tính:
a) \(\left(\frac{1}{3}-1\right).\left(\frac{1}{6}-1\right).\left(\frac{1}{10}-1\right).\left(\frac{1}{15}-1\right)...\left(\frac{1}{1225}-1\right).\left(\frac{1}{1275}-1\right)\)
b) 1 - 2 + 3 - 4 + 5 - 6 + ... + 2011 - 2012