Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) 528 = (52)14 = 2514
Vì 2514 < 2614 nên 528 < 2614
b) 530 = (53)10 = 12510
Vì 12510 > 12410 nên 530 > 12410
c) 421 = (43)7 = 647
Vì 647 = 647 nên 421 = 647
Mong mn ủng hộ mk
\(a,5^{28}=\left(5^2\right)^{14}=25^{14}< \)\(26^{14}\)
\(\Rightarrow5^{28}< 26^{14}\)
\(b,5^{30}=\left(5^3\right)^{10}=125^{10}>124^{10}\)
\(\Rightarrow5^{30}>124^{10}\)
\(c,4^{21}=\left(4^3\right)^7=64^7\)
\(\Rightarrow4^{21}=64^7\)
https://www.youtube.com/channel/UC5odkiOvzz9Rvu3HUYlL2IQ?view_as=subscriber
\(\text{Phần a nên sửa đề thế này :}\) \(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)
\(\text{Giải :}\)
\(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)
\(=\frac{1}{7}\left(\frac{-3}{8}+\frac{-13}{8}\right)\)
\(=\frac{1}{7}.\left(-2\right)\)
\(=\frac{-2}{7}\)
\(\frac{3}{5}.\frac{13}{46}-\frac{1}{10}.\frac{16}{23}\)
\(=\frac{3}{5}.\left(\frac{1}{46}.13\right)-\frac{1}{10}.\frac{32}{46}\)
\(=\left(\frac{3}{5}.13\right).\frac{1}{46}-\left(\frac{1}{10}.32\right).\frac{1}{46}\)
\(=\frac{39}{5}.\frac{1}{46}-\frac{32}{10}.\frac{1}{46}\)
\(=\frac{78}{10}.\frac{1}{46}-\frac{32}{10}.\frac{1}{46}\)
\(=\left(\frac{78}{10}-\frac{32}{10}\right).\frac{1}{46}\)
\(=\frac{46}{10}.\frac{1}{46}\)
\(=\frac{1}{10}\)
\(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)
\(=\frac{1}{7}\left(\frac{-3}{8}+\frac{-13}{8}\right)\)
\(=\frac{1}{7}.-2\)
\(=\frac{-2}{7}\)
\(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)
\(=\frac{1}{7}\left(\frac{-3}{8}+\frac{-13}{8}\right)\)
\(=\frac{1}{7}.\left(-2\right)\)
\(=\frac{-2}{7}\)
a) 2000.2000..>.. 1990.2010
b) 25.33 -10 ..<..31.26+10
d)32.53 -10 ..<..53.31+32
e) 1998.1998..>..1996.2000
-Bài này không có ý c hả bạn?
\(\text{Phần a :}\)
\(\frac{2}{3}.x=\frac{-4}{27}\)
\(\Rightarrow x=\frac{-4}{27}:\frac{2}{3}=\frac{-2}{9}\)
\(\text{Phần b :}\)
\(-1\frac{1}{3}.x=1\frac{1}{15}\)
\(\Rightarrow\frac{-4}{3}.x=\frac{16}{15}\)
\(\Rightarrow x=\frac{16}{15}:\frac{-4}{3}=\frac{-4}{5}\)
\(7^4=7^3\cdot7=7^3+7^3\cdot6>7^3+1\)