Kiếm điểm nè ! Dễ lắm òi . `A` `=` `{7×6^10×2^20×3^6-2^9×6^15}/{9×6^19×2^9-4×3^17×2^26}` 16/10/2021 Bởi Claire Kiếm điểm nè ! Dễ lắm òi . `A` `=` `{7×6^10×2^20×3^6-2^9×6^15}/{9×6^19×2^9-4×3^17×2^26}`
Đáp án: Ta có : $A = \dfrac{7.6^{10}.2^{20}.3^6-2^9.6^{15}}{9.6^{19}.2^9-4.3^{17}.2^{26}}$ $ = \dfrac{7.2^{10}.3^{10}.2^{20}.3^6-2^9.3^{15}.2^{15}}{3^2.3^{19}.2^{19}.2^9-2^2.3^{17}.2^{26}}$ $ = \dfrac{2^{30}.3^{16}.7-2^{24}.3^{15}}{2^{28}.3^{21}-2^{28}.3^{17}}$ $ = \dfrac{2^{24}.3^{15}.(2^6.3.7-1)}{2^{21}.3^{17}.(2^7.3^4-1)}$ $ = \dfrac{2^{24}.3^{15}.1343}{2^{21}.3^{17}.10367}$ $ = \dfrac{2^3.1343}{3^2.10367}$ $ = 0,11515171$ Bình luận
Giải thích các bước giải:
Đáp án:
Ta có : $A = \dfrac{7.6^{10}.2^{20}.3^6-2^9.6^{15}}{9.6^{19}.2^9-4.3^{17}.2^{26}}$
$ = \dfrac{7.2^{10}.3^{10}.2^{20}.3^6-2^9.3^{15}.2^{15}}{3^2.3^{19}.2^{19}.2^9-2^2.3^{17}.2^{26}}$
$ = \dfrac{2^{30}.3^{16}.7-2^{24}.3^{15}}{2^{28}.3^{21}-2^{28}.3^{17}}$
$ = \dfrac{2^{24}.3^{15}.(2^6.3.7-1)}{2^{21}.3^{17}.(2^7.3^4-1)}$
$ = \dfrac{2^{24}.3^{15}.1343}{2^{21}.3^{17}.10367}$
$ = \dfrac{2^3.1343}{3^2.10367}$
$ = 0,11515171$