a,6B=2.4.6+4.6.(8-2)+...............+98.100.(102-96)
6B=2.4.6+4.6.8-2.4.6+..............+98.100.102-96.98.100
6B=98.100.102
B=98.100.102:6
B=166600
3/3.6 + 3/6.9 + 3/9.12 + ... + 3/96.99
Rút gọn.
a,1.2+2.4+3.6+4.8+5.10 / 3.4+6.8+9.12+12.16+15.20
b, 12.13+24.26+36.39 / 24.26+48.52+72.78
c, 2.3+4.6+14.21 / 3.5+6.10+21.35
giúp mk nhé!ai nhanh mk k
B=\(\dfrac{1}{2.4}\)+\(\dfrac{1}{4.6}\)+\(\dfrac{1}{6.8}\)+\(\dfrac{1}{8.10}\)
A=1.2+2.3+3.4+.....+79.80
B=2.4+4.6+6.8+....+48.50
tìm B biết B=2^2/3.3^3/8^2.4^4/15^3.5^5/24^4.6^6/35^5.7^7/48^6.8^8/63^7.9^9/80^8
So sánh A và B biết : A = 1.2+2.4+3.6+4.8+5.10/3.4+6.8+9.12+12.16+15.20 va B = 111111/666665
Tính giá trị biểu thức
a) 2/5.1/3-2/15:1/5+3/5.1/3
b) 4/2.4+4/4.6+4/6.8+....+4/2008.2010
Bài 15 tính tổng a) A= 1/1.2 +1/2.3 +1/3.4 +...+1/2011.2012 b) B= 1/2.4 +1/4.6 + 1/6.8+.,.......+1/2010.2012
Rút gọn A =2.4+4.8+8.12+12.16+16.20/1.2+2.4+4.6+6.8+8.10
