Question

[Vũ Minh Nghĩa]

1/2 +2/3 +3/4 +4/5+..+99/100

1/99+2/98 +3/97+...+98/2+99/1

help me,ai giải nhanh nhất tớ tick cho

Answer 1

[tranmanhtuan]

câu 1 :1/100

câu 2 :1

Answer 2

[Lê Anh Tú]

b)ta đặt A:  \(A=\frac{1}{99}+\frac{2}{98}+..+\frac{99}{1}\)

                   \(A=\left(\frac{1}{99}+1\right)+\left(\frac{2}{98}+1\right)+..+\left(\frac{98}{2}+1\right)+\left(\frac{99}{1}-98\right)\)

                  \(A=\frac{100}{99}+\frac{100}{98}+..+\frac{100}{2}+\frac{100}{100}\)

                  \(A=100\cdot\left(\frac{1}{100}+\frac{1}{99}+\frac{1}{98}+..+\frac{1}{2}\right)\)