( 1 + 1/51 ) X ( 1 + 1/52) X ( 1 + 1/53 )
2/3*x-(1/2-3/4+5/6-7/8+...+197/198-199/200)=1/51+1/52+1/53+...+1/99+1/100
Tìm x
viết có chắc chữ giải mà cũng đúng thật vô lý
tinh bang cach hop li
a) (1+1/51) x (1+1/52) x (1+1/53) .....( (1+1/1963)
b) (1+1/400) x (1+1/401) x (1+1/402) ...... (1-1/2010)
tinh bang cach hop li
a) (1+1/51) x (1+1/52) x (1+1/53) .....( (1+1/1963)
b) (1+1/400) x (1+1/401) x (1+1/402) ...... (1-1/2010)
tinh bang cach hop li
a) (1+1/51) x (1+1/52) x (1+1/53) .....( (1+1/1963)
b) (1+1/400) x (1+1/401) x (1+1/402) ...... (1-1/2010)
a)
\(\left(1+\frac{1}{51}\right).\left(1+\frac{1}{52}\right).\left(1+\frac{1}{53}\right)...\left(1+\frac{1}{1963}\right)\)
\(=\frac{52}{51}.\frac{53}{52}.\frac{54}{53}...\frac{1964}{1963}\)
\(=\frac{1964}{51}\)
b)
\(\left(1+\frac{1}{400}\right).\left(1+\frac{1}{401}\right).\left(1+\frac{1}{402}\right)...\left(1+\frac{1}{2010}\right)\)
\(=\frac{401}{400}.\frac{402}{401}.\frac{403}{402}...\frac{2011}{2010}\)
\(=\frac{2011}{400}\)
1/51 + 1/52 + 1/53 + ... + 1/100
1/51 + 1/52 +1/53 +...+1/100 =?
Chứng minh : 51/2 x 52/2 x 53/2 x.......x 100/2 = 1 x 3 x 5 x 7 x.......x 99
1.3.5.7........99 = \(\frac{\left(1.3.5.7......99\right)\left(2.4.6......100\right)}{2.4.6......100}\)= \(\frac{1.2.3......99.100}{2^{50}\left(1.2.3.....50\right)}=\frac{51.52.53.......100}{2.2.2......2}=\frac{51}{2}.\frac{52}{2}....\frac{100}{2}\)(ĐPCM)
50 số 2
Tính tổng 1/51+1/52+1/53+...+1/99+1/100
Ta có:\(\frac{1}{51}+\frac{1}{52}+...+\frac{1}{100}=\left(1+\frac{1}{2}+...+\frac{1}{100}\right)-\left(1+\frac{1}{2}+...+\frac{1}{50}\right)=\left(1+\frac{1}{2}+...+\frac{1}{100}\right)-2.\left(\frac{1}{2}+\frac{1}{4}+...+\frac{1}{100}\right)\)
\(=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{99}-\frac{1}{100}=1-\frac{1}{100}=\frac{99}{100}\)
@Ác Mộng ở đoạn cuối tự nhiên bỏ mất số 2 luôn, giải sai rồi kìa
Tính A=1/51+1/52+1/53+...+1/99+1/100