Đáp án:
Giải thích các bước giải:
12 . $\frac{64}{8^4}$ = 12 . $\frac{8}{8^3}$
= 12 . $\frac{1}{8^2}$
= 12 . $\frac{1}{64}$
= $\frac{12}{64}$
= $\frac{3}{16}$
13 . $\frac{6^4}{216}$ = 13 . $\frac{6^3}{36}$
= 13 . $\frac{6^2}{6}$
= 13 . 6
= 78
14 . $\frac{8^6}{256}$ = 14 . $\frac{8^5}{32}$
= 14 . $\frac{8^4}{4}$
= 14 . `8^3` . 2
= 14 . 1024
= 14336
15 . $\frac{11^4}{121}$ = 15 . $\frac{11^3}{11}$
= 15 . 11^2
= 15 . 121
= 1815
16 . $\frac{144}{12^4}$ = 16 . $\frac{12}{12^3}$
= 16 . $\frac{1}{12^2}$
= 16 . $\frac{1}{144}$
= $\frac{16}{144}$
= $\frac{1}{9}$
17 . $\frac{196}{14^6}$ = 17 . $\frac{14}{14^5}$
= 17 . $\frac{1}{14^4}$
= 17 . $\frac{1}{38416}$
= $\frac{17}{38416}$
18 . $\frac{15^4}{225}$ = 18 . $\frac{15^3}{15}$
= 18 . `15^2`
= 18 . 225
= 4050
19 . $\frac{256}{16^3}$ = 19 . $\frac{16}{16^2}$
= 19 . $\frac{1}{16}$
= $\frac{19}{16}$
20 . $\frac{(-5)^3}{125}$ = 20 . ( -1 )
= - 20
21 . $\frac{(-5)^7}{625}$ = 21 . (-125)
= - 2625
22 . $\frac{49}{(-7)^5}$ = 22 . $\frac{-1}{343}$
= $\frac{-22}{343}$
23 . $\frac{18}{(-9)^3}$ = 22 . $\frac{-2}{81}$ = $\frac{-44}{81}$
