Question

Tính :

  a) \(1\frac{1}{3}\) x \(1\frac{1}{8}\) x \(1\frac{1}{15}\) x \(1\frac{1}{24}\) x ................x \(1\frac{1}{99}\)

  b) \(\frac{99}{98}\) - \(\frac{98}{97}\) + \(\frac{1}{97\cdot98}\)

Answer 1

a) \(1\frac{1}{3}.1\frac{1}{8}.1\frac{1}{15}.1\frac{1}{24}.........1\frac{1}{99}\)

\(=\frac{4}{3}.\frac{9}{8}.\frac{16}{15}.\frac{25}{24}......\frac{100}{99}\)

\(=\frac{\left(2.2\right).\left(3.3\right).\left(4.4\right).\left(5.5\right)....\left(10.10\right)}{\left(1.3\right).\left(2.4\right).\left(3.5\right).\left(4.6\right).....\left(9.11\right)}\)

\(=\frac{\left(2.3.4.5...10\right).\left(23.4.5....10\right)}{\left(1.2.3.4...9\right).\left(3.4.5.6....11\right)}=\frac{10}{1}.\frac{2}{11}=\frac{20}{11}\)

Answer 2

b) \(\frac{99}{98}-\frac{98}{97}+\frac{1}{97.98}=\frac{99}{98}-\frac{98}{97}+\frac{1}{97}-\frac{1}{98}=\left(\frac{99}{98}-\frac{1}{98}\right)-\left(\frac{98}{97}-\frac{1}{97}\right)\)

\(=\frac{98}{98}-\frac{97}{97}=1-1=0\)

Answer 3

a)  \(\frac{20}{11}\)

b) 0

Answer 4

Bạn nào giúp mình trả lời thì nhớ là 97 x 98 nha

Answer 5

Nhảm thật, lm đầy đủ ko tick, đi tick cho lũ copy đáp án