\(A=2^{2017}+2^{2016}+...+2+1\)
\(\Leftrightarrow2A=2^{2018}+2^{2017}+...+2^2+2\)
\(\Leftrightarrow A=2^{2018}-1\)
\(B=2^{2018}-2^{2017}-2^{2016}-...-2-1\)
\(=2^{2018}-A=1\)
Tính giá trị của :
D=\(\left(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+...+\frac{1}{2019^2}\right)x\left(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{2020^2}\right)-\left(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+...+\frac{1}{2020^2}\right)x\left(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{2019^2}\right)\)
\(M=\left(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+....+\frac{1}{2020^2}\right)X\left(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{2020^2}\right)-\left(\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+...+\frac{1}{2020^2}\right)X\left(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+...+\frac{1}{2020^2}\right)\)Làm nhanh và ngắn gọn nhất có thể nhé ! mình tik cho 10 tik
tính : ( 1-1/3^2 ) . (1-1/4^2 ) . ( 1-1/5^2) .(1-1/6^2).(1-1/7^2).(1-1/8^2)
Chứng minh rằng: S=1+1/2^2+1/3^2+1/4^2+1/5^2+1/6^2+1/7^2+1/8^2+1/9^2+1/10^2 < 2
Giúp vs nha mấy bn ! Thanks!!!!!!!!!!!
1)CMR
a) 1/2^2 +1/3^2+......+1/2018^2 < 1
b) 1/2^2 +1/4^2+1/6^2+......+1/2018^2<1/2
c)E=1/2^2+1/3^2+....+1/100^2<3/4
Giúp mình với m đang cần gấp lắm 😱😱😱
Tính :
A= (1-1/3^2) . (1-1/4^2) . (1-1/5^2) . ( 1 - 1/16^2) . ( 1-1/7^2) . ( 1-1/8^2)
tính :
A= (1-1/3^2) . (1-1/4^2) . (1-1/5^2) . ( 1 - 1/16^2) . ( 1-1/7^2) . ( 1-1/8^2)
tính :
A= (1-1/3^2) . (1-1/4^2) . (1-1/5^2) . ( 1 - 1/16^2) . ( 1-1/7^2) . ( 1-1/8^2)
1) tính: 1+ 1/2+ 1/2^2+..........................+ 1/2^99 + 1/2^100 + 1/2^100
cm 1/2- 1/2^2+1/2^3-1/2^4+1/2^5-1/2^6 <1/3
help
