tách tất cả ra là dc rễ vvvvvvvvvvvvvvvvvv

\(\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^{10}.6^{19}-7.2^{29}.27^6}=\frac{5.2^{30}.3^{18}-3^{20}.2^{29}}{5.2^{29}.3^{19}-7.2^{29}.3^{18}}\)

\(=\frac{2^{29}.3^{18}.\left(5.2-9\right)}{2^{29}.3^{18}.\left(5.3-7\right)}=1\)

5.4¹⁵.9⁹-4.3²⁰.8⁹                             5.2³⁰.3¹⁸-2².3²⁰.2²⁷                            5.2³⁰.3¹⁸-2².3²⁰.2²⁷                5.2³⁰.3¹⁸-2².2²⁷.3²⁰  

^{------------------------}                  = --------------------------------------   =        --------------------------------------  =--------------------------------------

5.2¹⁰.6¹⁹-7.2²⁹.27⁶                    5.2¹⁰.(2.3)¹⁹-7.2²⁹.3¹⁸                          5.2¹⁰.2¹⁹.3¹⁹-7.2²⁹.3¹⁸         5.2²⁹.3¹⁹-7.2²⁹.3¹⁸

                                                                                                                                  =       5.2³⁰.3¹⁸-2²⁹.3²⁰    

                                                                                                                                      --------------------------------------

                                                                                                                                            5.2²⁹.3¹⁹-7.2²⁹.3¹⁸

                                                                             làm nốt nha!!

\(\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5\cdot2^{10}\cdot6^{19}-7.2^{29}.27^6}\) 

\(=\frac{5.2^{30}.3^{18}-2^2.3^{20}.2^{27}}{5.2^9.2^{19}-7.2^{29}.3^{18}}\) 

\(=\frac{5.2^{30}.3^{18}-2^{29}.3^{20}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}\) 

\(=\frac{2^{29}.3^{18}\left(5.2-3^2\right)}{2^{28}.3^{18}\left(5.3-7.2\right)}\) 

\(=\frac{2.\left(10-9\right)}{15-14}\) 

\(=2\) 

Vậy BT trên có giá trị là: 2

Đề bài sai chỗ ... - 9⁹ nhé, nếu là .9⁹ sẽ hợp lí hơn =))

\(A=\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^{10}.6^{19}-7.2^{29}.27^6}=\frac{5.\left(2^2\right)^{15}\left(3^2\right)^9-2^2.3^{20}.\left(2^3\right)^9}{5.2^{10}.\left(2.3\right)^{19}-7.2^2.\left(3^2\right)^6}\)

\(A=\frac{5.2^{30}.3^{18}-2^2.3^{20}.2^{27}}{5.2^{10}.2^{19}.3^{19}-7.2^{29}.3^{18}}\)

\(A=\frac{5.2^{30}.3^{18}-2^{29}.3^{20}}{5.2^{29}.3^{19}-7.2^{29}.3^{18}}\)

\(A=\frac{2^{29}.3^{18}.\left(5.2-3^2\right)}{2^{29}.3^{18}.\left(5.3-7\right)}\)

\(A=\frac{10-9}{15-7}=\frac{1}{8}\)

\(\dfrac{5.4^{15}.9^9+4.3^{20}.8^9}{5.2^{10}.6^{19}-7.2^{29}.27^6}=\dfrac{5.2^{30}.3^{18}+2^2.3^{20}.2^{27}}{5.2^{10}.2^{19}.3^{19}-7.2^{29}.3^{18}}\)

=\(\dfrac{5.2^{30}.3^{18}+2^{29}.3^{20}}{5.2^{29}.3^{19}-7.2^{29}.3^{18}}=\dfrac{2^{29}.3^{18}\left(5.2+3^2\right)}{2^{29}.3^{18}\left(5.3-7\right)}\)

=\(\dfrac{10+9}{15-7}=\dfrac{19}{8}\)

\(\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^9.6^{19}-7.2^{29}.27^6}=\frac{5.\left(2^2\right)^{15}.\left(3^2\right)^9-2^2.3^{20}.\left(2^3\right)^9}{5.2^9.3^{19}.2^{19}-7.2^{29}.\left(3^3\right)^6}=\frac{5.2^{30}.3^{18}-2^2.3^{20}.2^{27}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}=\frac{5.2^{30}.3^{18}-2^{29}.3^{20}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}=\frac{3^{18}.\left(5.2^{30}-2^{29}.3^2\right)}{3^{18}.\left(5.2^{28}.3-7.2^{29}\right)}=\frac{2^{28}.\left(5.2\right)}{2^{28}\left(5.3-7.2\right)}=\frac{10}{15-14}=\frac{10}{1}=10\)

Có j sai mong bỏ qua

Học tốt

B= {[ 5 * (2^2)^15 * (3^2)^9 ] - [ (2^2) * 3^20 * (2^3)^9 ]} / {[ 5 * (2^9) * (2^19)*(3^19) ] - [ 7 * (2^29) * (3^3)^6 ]} 
B= {[ 5 * (2^30) * (3^18) ] - [ (3^20) * (2^29) ]} / {[ 5 * (2^28) * (3^19) ] - [ 7 * (2^29) * (3^18) ]} 
B= {[ (2^29) * (3^18) ] * [(5 * 2) - 3^2 ]} / {[ (2^28) * (3^18) ] - [(5 * 3) - (7 * 2)] } 
B= [ (2^29) * (3^18) ] / [ (2^28) * (3^18) ] 
B= [ (2^1) * (2^28) * (3^18) ] / [ (2^28) * (3^18) ] 
B = 2

ta có \(\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^9.6^{19}-7.2^{29}.27^6}\)=\(\frac{5.2^{30}.3^{18}-2^2.3^{20}.2^{27}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}\)=\(\frac{2^{29}.3^{18}\left(2.5-3^2\right)}{2^{28}.3^{18}\left(5.3-7.2\right)}\)=2