So sánh \(\frac{-19}{49}\)và\(\frac{-23}{27}\)

Quy đồng lên ta được: \(\frac{-19}{49}=\frac{\left(-19\right).47}{49}=\frac{-893}{2303}\)và\(\frac{-23}{47}=\frac{\left(-23\right).49}{47.49}=\frac{-1127}{2303}\)

Mà: \(\frac{-893}{2303}>\frac{-1127}{2303}\)\(\Rightarrow\frac{-19}{49}>\frac{-23}{47}\)

em làm xong từ hôm qua r ạ

\(\frac{84}{-83}=\frac{-84}{83}\)

\(\frac{-84}{83}+\frac{1}{83}=-1\)

\(\frac{-337}{331}+\frac{6}{331}=-1\)

\(\frac{1}{83}< \frac{6}{331}\Rightarrow\frac{84}{-83}>\frac{-337}{331}\)

Xin lỗi mink mới học lớp 5 năm nay lên lớp 6 mink ko thể giúp bn đc sorry nha! 

-25/20 < 20/25

15/21 > 21/49

\(a.\)

\(625^{17}=\left(5^4\right)^{17}=5^{68}\)

\(125^{19}=\left(5^3\right)^{19}=5^{57}\)

Vì \(5^{68}>5^{57}\Rightarrow625^{17}>125^{19}\)

Ta có:\(\frac{-157}{623}=\frac{-331441}{132699}\)

           \(\frac{-47}{213}=\frac{-29281}{132699}\)

  Vì \(-331441< -29281\)nên\(\frac{-331441}{132699}< \frac{-29281}{132699}\)

                                                     hay\(\frac{-157}{623}< \frac{-47}{213}\)

              Vậy \(\frac{-157}{623}< \frac{-47}{213}\)

\(\frac{-157}{623}< \frac{-47}{213}\)

\(\sqrt{\frac{\left(-5\right)^2}{7}}=\frac{\sqrt{\left(-5\right)^2}}{\sqrt{7}}=\frac{|5|}{\sqrt{7}}=\frac{5\sqrt{7}}{7}\)

\(\frac{-\sqrt{\left(-5\right)^2}}{-\sqrt{49}}=\frac{\sqrt{\left(-5\right)^2}}{\sqrt{49}}=\frac{|5|}{|7|}=\frac{5}{7}\)

\(\frac{5\sqrt{7}}{7}>\frac{5}{7}\leftrightarrow\sqrt{\frac{\left(-5\right)^2}{7}}>\frac{-\sqrt{\left(-5\right)^2}}{-\sqrt{49}}\)

Ta có:

2⁹⁸ < 2⁹⁹ = (2¹¹)⁹ = 2048⁹

5⁴⁷ > 5⁴⁵ = (5⁵)⁹ = 3125⁹

Vì 2⁹⁸ < 2048⁹ < 3125⁹ < 5⁴⁷

=> 2⁹⁸ < 5⁴⁷

cám ơn bạn nha

đặt \(A=\frac{10^{18}+1}{10^{19}+1};B=\frac{10^{19}+1}{10^{20}+1}\)

ta có: \(10A=\frac{10^{19}+1+9}{10^{19}+1}=1+\frac{9}{10^{19}+1}\)

\(10B=\frac{10^{20}+1+9}{10^{20}+1}=1+\frac{9}{10^{20}+1}\)

mà \(\frac{9}{10^{19}+1}>\frac{9}{10^{20}+1}\)

=> 10A >10B

=> A > B