tính : A= (1-1/4) . (1-1/9) . (1-1/16) ...(1-1/10000)
A=(1-1/4).(1-1/9).(1-1/16).(1-1/25)...(1-1/10000)
So sánh :(1-1/4)(1-1/9)(1-1/16)......(1-1/10000) với 1/2
Tính các tích sau:
A= 3/4.8/9.15/16...9999/10000
B=(1-1/4).(1-1/9)...(1-1/10000).
C=(1+1/1.3)(1+1/2.4)(1+1/3.15)....(1+1/99.100).
\(\left(1-\dfrac{1}{4}\right)\left(1-\dfrac{1}{9}\right)\left(1-\dfrac{1}{16}\right).....\left(1-\dfrac{1}{10000}\right)\)
1) Tính
A= 3/4.8/9.15/16...9999/10000
B= (1-1/4).(1-1/9)...(1-1/1000)
A = 1/10 + 1/40 + 1/88 + 1/154 + 1/238 + 1/340
B = 3/4 . 8/9 .15/16. ... 9999/10000
1+4+9+16+25+...+10000
Chứng minh rằng
\(\frac{1}{4}+\frac{1}{9}+\frac{1}{16}+...+\frac{1}{10000}