A = ( 1/3 - 1).( 1/6 - 1).( 1/10 - 1).( 1/15 - 1).( 1/21 - 1).( 1/28 - 1).( 1/36 - 1)

A = -2/3 . ( -5/6) . ( -9/10) . ( -14/15) . ( -20/21) . ( -27/28) . ( -35/36)

Do tích A có lẻ thừa số, mỗi thừa số đều mang dấu âm nên A mang dấu âm

A = -[ 2/3 . 5/6 . 9/10 . 14/15 . 20/21 . 27/28 . 35/36]

Đặt B = 2/3 . 5/6 . 9/10 . 14/15 . 20/21 . 27/28 . 35/36

B = 4/6 . 10/12 . 18/20 . 28/30 . 40/42 . 54/56 . 70/72

B = 1.4/2.3  .  2.5/3.4  .  3.6/4.5  .  4.7/5.6  .  5.8/6.7  .  6.9/7.8  .  7.10/8.9

B = 1.2.3.4.5.6.7/3.4.5.6.7.8.9  .  4.5.6.7.8.9.10/2.3.4.5.6.7.8

B = 2/8.9  .  9.10/2.3

B = 5/12

A = -5/12

cÓ ĐÚNG KO VẬY P NẾU ĐÚNG THÌ CHO MIK THANK Y NHA

A=-5/12

Khó lắm Tùng Ams, k nha

F=(6/8+1)(6/18+1)(6/30+1)...(6/10700+1)

       14.24.36...10706

F=  ---------------------------

        8.18.30....10700

      7.2.8.3.9.4...106.101

F= -----------------------------------

     8.1.9.2.10.3...107.100

      (7.8.9....106)(2.3.4...101)

F= ----------------------------------------

      (8.9.10...107)(2.3.4...100)

      7.101

F= ----------

      107

F=1

Mình nhầm nhé! Bạn để nguyên:

F =707/101 là được rồi

K mình nhé!

a, \(\frac{\left(\frac{1}{9}\right)^6\cdot\left(\frac{3}{8}\right)^7}{\left(\frac{1}{3}\right)^{13}\cdot\left(\frac{1}{2}\right)^{22}.3^6}\)

\(=\frac{\left(\frac{1}{\left(3^2\right)^6}\right)\cdot\left(\frac{1}{2}\cdot\frac{1}{2}\cdot\frac{1}{2}\cdot3\right)^7}{\left(\frac{1}{3}\right)^{13}.\left(\frac{1}{2}\right)^{22}.3^6}=\frac{\frac{1}{3^{12}}\cdot\left(\frac{1}{2}\right)^{21}\cdot3^7}{\frac{1}{3^{13}}\cdot\left(\frac{1}{2}\right)^{22}.3^6}\)

                                                              \(=\frac{3}{\frac{1}{3}\cdot\frac{1}{2}}=3\div\frac{1}{6}=3.6=18\)

b, Làm tương tự nha bn