Question

[nguyễn hoàng lê thi]

Viết các biểu thức số sau dưới dạng aⁿ (a \(\in\) Q , n \(\in\) N):

a) 9 . 3³ . \(\frac{1}{81}\) . 3²

b) 4 . 2⁵ : \(\left(2^3.\frac{1}{16}\right)\)

c) 3² . 2⁵ . \(\left(\frac{2}{3}\right)^2\)

d) \(\left(\frac{1}{3}\right)^2\) . \(\frac{1}{3}\) . 9²

^{MONG CÁC BN GIÚP ĐỠ MK BÀI NÀY VS.}

Answer 1

[Bạch Y]

a) \(9\cdot3^3\cdot\frac{1}{81}\cdot3^2=3^2\cdot3^3\cdot\left(\frac{1}{3}\right)^43^2=3^7\cdot\frac{1}{3^4}=3^3\)

b) \(4\cdot2^5:\left(2^3\cdot\frac{1}{16}\right)=2^2\cdot2^5:\left(2^3\cdot\frac{1}{2^4}\right)=2^7:\frac{1}{2}=2^8\)

c) \(3^2\cdot2^5\cdot\left(\frac{2}{3}\right)^2=3^2\cdot2^5\cdot\frac{2^2}{3^2}=2^7\)

d) \(\left(\frac{1}{3}\right)^2\cdot\frac{1}{3}\cdot9^2=\frac{1}{3^2}\cdot\frac{1}{3}\cdot3^4=\frac{1}{3^3}\cdot3^4=3\)

Answer 2

[Nobi Nobita]

a)9.3³.\(\frac{1}{81}\).3²

   =3².3³.3⁴.\(\frac{1}{3^4}\).3²

    ⁼3¹¹.\(\frac{1}{3^4}\)

    =3⁷

b)4.2⁵:(\(2^3.\frac{1}{16}\))

  =2².2⁵:(\(2^3.\frac{1}{2^4}\))

  =2⁷:\(\frac{2^3}{2^4}\)

  =2⁷.\(\frac{2^4}{2^3}\)

   =\(\frac{2^{11}}{2^3}\)

   =2⁸

c)3².2⁵.\(\left(\frac{2}{3}\right)^2\)

   =3².2⁵.\(\frac{2^2}{3^2}\)

   =\(\frac{3^2.2^5.2^2}{3^2}\)

   =2⁷

d)\(\left(\frac{1}{3}\right)^2.\frac{1}{3}.9^2\)

    =\(\frac{1^2}{3^2}.\frac{1}{3}.\left(3^2\right)^2\)

    =\(\frac{1^2}{3^2}.\frac{1}{3}.3^4\)

    =\(\frac{1^2}{3^2}.\frac{3^4}{3}\)

    =\(\frac{1^2}{3^2}.3^3\)

   =3