a. \(27^{11}=\left(3^3\right)^{11}=3^{3\cdot11}=3^{33}\)
\(81^8=\left(3^4\right)^8=3^{4\cdot8}=3^{32}\)
Vì 32<33 => 3³²<3³³ => 81⁸<27¹¹
b. \(63^{15}=\left(63^5\right)^3=992436543^3\)
\(34^{18}=\left(34^6\right)^3=1544804416^3\)
Vì 992436543<1544804416 nên 992436543³<1544804416³ => \(63^{15}< 34^{18}\)

1) 63¹⁵ < 64¹⁵  = (2⁶)¹⁵ = 2⁹⁰

34¹⁸ > 32¹⁸ = (2⁵)¹⁸ = 2⁹⁰

=> 63¹⁵ < 2⁹⁰ < 34¹⁸ . Vậy 63¹⁵ < 34¹⁸

2) 83⁹ > 81⁹ = (3⁴)⁹ = 3³⁶

26¹² < 27¹² = (3³)¹² = 3³⁶

=> 26¹² < 3³⁶ < 83⁹ . Vậy 26¹² < 83⁹

63 ^15 = 60 ^ 5*3 = (65^5 ) ^3 = 992436543^3

34^18 = 34 ^6*3 = (34^6)^3 = 1544804416^3

vì  992436543^3 < 1544804416^3

=> 63 ^ 15 < 34 ^ 18 

k mk nha mn 

Ta có:

 \(63^{15}< 64^{15}\)

\(=\left(2^6\right)^{15}\)

\(=2^{90}\)

\(=\left(2^5\right)^{18}\)

\(=32^{18}< 34^{18}\)

\(\Rightarrow63^{15}< 34^{18}\)

63=3^2.7 

mà bạn

1) 63¹⁵ < 64¹⁵  = (2⁶)¹⁵ = 2⁹⁰

34¹⁸ > 32¹⁸ = (2⁵)¹⁸ = 2⁹⁰

=> 63¹⁵ < 2⁹⁰ < 34¹⁸ . Vậy 63¹⁵ < 34¹⁸

2) 83⁹ > 81⁹ = (3⁴)⁹ = 3³⁶

26¹² < 27¹² = (3³)¹² = 3³⁶

=> 26¹² < 3³⁶ < 83⁹ . Vậy 26¹² < 83⁹

mk ko biết giai thông cảm

63^15<34^18

63 ^15 = 63^ 5.3 = ( 63^ 5 ) 3 = 992 436 543^ 3

34 ^18 = 34^ 6.3 = ( 34^ 6 ) 3 = 1 544 804 416 ^3

Vì : 992 436 543^ 3 < 1 544 804 416^ 3

Nên : 63 ^15 < 34^ 18 

63 mũ 15 >34 mũ 18

thanks