A= 1/5.9+1/9.13+1/13.17+1/17.21+1/21.25
4A= 4/5.9+4/9.13+4/13.17+4/17.21+4/21.25
4A= (1/5-1/9)+(1/9-1/13)+(1/13-1/17)+(1/17-1/21)+(1/21-1/25)
4A= 1/5- 1/25
4A= 4/25
A= 4/25 :4
A= 1/25
B=1/1.5+1/5.9+1/9..13+1/13.17+1/17.21+1/21.25+1/25.29
1/1.5 + 1/5.9 + 1/9.13 + 1/13.17 + .....+ 1/41.45
cb kb với mk nha
Tinh
A= 4/5.9 + 4/9.13 + 4/13.17 + ....+ 4/41.45
B= ( 1 - 1/2 ) . ( 1 - 1/3 ) . ( 1 - 1/4 ) ...... ( 1 - 1/100 )
\(\frac{7}{1.5}\)+ \(\frac{7}{5.9}\)+ \(\frac{7}{9.13}\)+\(\frac{7}{13.17}\)+ \(\frac{7}{17.21}\)
help me!!!!!
1/5.9+1/1.13+1/13.17+ ...+1/41.45
1/1.5+1/5.9+1/9.13+...+1/97.101
Giải giúp mik bài toán
1/1.5+1/5.9+1/9.13+..+1/97.101
Cảm ơn nhiều^^
Tính nhanh : ( Lưu ý : dấu ( . ) là dấu nhân )
\(A=\frac{1}{5.9}+\frac{1}{9.13}+\frac{1}{13.7}+...............+\frac{1}{100.104}\)
Tính nhanh:
H=2.2/1.5+2.2/5.9+2.2/9.13+......................+2.2/45.49
LƯU Ý: DẤU CHẤM LÀ NHÂN
