Question

[Hoàng Ngọc Nam]

a) Cho :

A = 5 x 4¹⁵ x 9⁹ - 4 x 3²⁰ x 8⁹

B = 5 x 2⁹ x 6¹⁹ - 7 x 2²⁹ x 27⁶

Tính A : B

Ai giải đúng mình mới tích nhé

Answer 1

[Minh Triều]

\(\frac{A}{B}=\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^9.6^{19}-7.2^{29}.27^6}\)

\(=\frac{5.\left(2^2\right)^{15}.\left(3^2\right)^9-2^2.3^{20}.\left(2^3\right)^9}{5.2^9.2^{19}.3^{19}-7.2^{29}.\left(3^3\right)^6}\)

\(=\frac{5.2^{30}.3^{18}-2^{29}.3^{20}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}=\frac{2^{29}.3^{18}.\left(5.2-3^2\right)}{2^{28}.3^{18}.\left(5.3-7.2\right)}\)

\(=\frac{2^{29}.3^{18}.1}{2^{28}.3^{18}.1}=2\)

Answer 2

[nguyen ngoc son]

A = 5 x 4¹⁵ x 9⁹ - 4 x 3²⁰ x 8⁹ = 5 x 2³⁰ x 3¹⁸- 2² x 2²⁷ x 3²⁰

 =2²⁹ x 3¹⁸ x(2x5-3²)=2²⁹ x 3¹⁸

B = 5 x 2⁹ x 6¹⁹ - 7 x 2²⁹ x 27⁶=5 x 2⁹ x 2¹⁹ x 3¹⁹ - 7 x 2²⁹ x 3¹⁸

=2²⁸ x 3¹⁸ x (5 x 3-7 x 2)= 2²⁸.3¹⁸

=>A:B= 2^29.3¹⁸:2²⁸:3¹⁸=2