a)  1 . 10 2 + 2 . 10 1 + 6 . 10 0

b)  1 . 10 4 + 6 . 10 2 + 8 . 10 0

9¹² x 27⁵ = (3²)¹² x (3³)⁵ = 3²⁴ x 3¹⁵ = 3²⁴⁺¹⁵ = 3³⁹

Chọn D

D. 3³⁹

Ta có:

 \(9^{12}.27^5=\left(3^2\right)^{12}.\left(3^3\right)^5=3^{2.12}.3^{3.5}=3^{24}.3^{15}=3^{24+15}=3^{39}\)

Vậy đáp án là D

a) 126 = 1 . 10 2 + 2 . 10 1 + 6 . 10 0

b) 1068 =  1 . 10 3 + 6 . 10 1 + 8 . 10 0

c,  a 0 b =  a . 10 2 + b . 10 0

d,  a 0 b c =  a . 10 3 + b . 10 1 + c . 10 0

a: \(A=8^2\cdot32^4=2^6\cdot2^{20}=2^{26}\)

b: \(B=27^3\cdot9^4\cdot243=3^9\cdot3^8\cdot3^5=3^{22}\)

a) \(9^3\cdot3^2\)

\(=\left(3^2\right)^3\cdot3^2\)

\(=3^6\cdot3^2\)

\(=3^8\)

b) \(x^7\cdot x:x^4\)

\(=x^8:x^4\)

\(=x^4\)

c) \(7\cdot3^9+3^{10}+51\cdot3^8\)

\(=3^8\cdot\left(7\cdot3+3^2+51\right)\)

\(=3^8\cdot81\)

\(=3^8\cdot3^4\)

\(=3^{12}\)

d) \(5^{15}\cdot125^3\cdot625\)

\(=5^{15}\cdot5^9\cdot5^4\)

\(=5^{28}\)

a. 8². 32⁴ = 2⁶. 2²⁰ = 2²⁶

b. 27³. 9⁴. 243 = 3⁹. 3⁸. 3⁵ = 3²²

c. 5 .125 . 625 = 5 . 5³. 5⁴ = 5⁸

d.10 . 100 . 1000 = 10 . 10². 10³ = 10⁶

e. 8⁴. 16⁵. 32 = 2¹². 2²⁰. 2⁵ = 2³⁷

f. 27⁴ . 81¹⁰ = 3¹². 3⁴⁰ = 3⁵²

=(12*3)^3

=36^3

12^3 x 3^3 

= ( 12 x 3 )^3

= 36 ^3

\(12^3.3^3=36^3=\left(6^2\right)^3=6^6\)

a: \(A=\left(2^3\right)^2\cdot\left(2^5\right)^4=2^6\cdot2^{20}=2^{26}\)

b: \(=\left(3^3\right)^3\cdot\left(3^2\right)^4\cdot3^5=3^9\cdot3^8\cdot3^5=3^{22}\)

\(A=8^2.32^4=\left(2^3\right)^2.\left(2^5\right)^4=2^6.2^{20}=2^{26}\)

\(B=27^3.9^4.243=\left(3^3\right)^3.\left(3^2\right)^4.3^5=3^9.3^8.3^5=3^{22}\)

a, 3⁴.27⁵.(3²)³ = 3⁴.(3³)⁵.3⁶ = 3⁴.3¹⁵.3⁶ = 3²⁵

b, (2³)⁴.4⁶.32 = 2¹².2¹².2⁵ = 2²⁹

c, 3²⁰¹⁹.6²⁰¹⁹: 2²⁰¹⁹ = 3²⁰¹⁹.3²⁰¹⁹.2²⁰¹⁹:2²⁰¹⁹ = (3.3)²⁰¹⁹= 9²⁰¹⁹

d, 125⁸.(5²)⁴ = (5³)⁸.5⁸ = 5³²