C= \(\frac{49}{200}\)
D= \(\frac{33}{100}\)
Chúc bạn Hk tốt!!!!
C =1/2*4+1/4*6+1/6*8+...+1/98*100
2xC=2/2*4+2/4*6+2/6*8+...+2/98*100
2xC=1/2-1/4+1/4-1/6+1/6-1/8+...+1/98-1/100
2xC=1/2-1/100
2xC=49/100
C=49/100:2
C=49/200
Ý B làm tương tự nhưng nhưng cả 2 vế với 3
nha. ^_^ ^_^ ^_^
\(C=\frac{1}{2\cdot4}+\frac{1}{4\cdot6}+......+\frac{1}{96\cdot98}+\frac{1}{98\cdot100}\)
\(2C=\frac{2}{2\cdot4}+\frac{2}{4\cdot6}+.......+\frac{2}{96\cdot98}+\frac{2}{98\cdot100}\)
\(2C=\frac{1}{2}-\frac{1}{4}+\frac{1}{4}-\frac{1}{6}+.....+\frac{1}{96}-\frac{1}{98}+\frac{1}{98}-\frac{1}{100}\)
\(2C=\frac{1}{2}-\frac{1}{100}\)
