Question

tính giá trị các biểu thức sau:

a) \(A=\dfrac{2^{15}.9^4}{6^6.8^3}\)

b) \(B=\dfrac{4^6.9^5+6^9.120}{-8^4.3^{12}-6^{11}}\)

c) \(C=\dfrac{4^5.9^4-2.6^9}{2^{10}.3^8+6^8.20}\)

có bn nào lm dc thì lm giúp mk vs nha mai mk nộp bài r

Answer 1

a)\(\dfrac{2^{15}.3^8}{2^6.3^6.2^9}\)\(\dfrac{ }{ }\)=\(^{3^2}\)=9

b)\(\dfrac{2^{12}.3^{10}+2^9.3^9.2^3.15}{-2^{12}.3^{12}-2^{11}.3^{11}}\)=\(\dfrac{2^{11}.3^{11}.\left(1+15\right)}{2^{11}.3^{11}\left(-2.3-1\right)}\)

=\(\dfrac{32}{-21}\)

c)\(\dfrac{2^{10}.3^8-2^{10}.3^9}{2^{10}.3^8+2^8.3^8.2^2.5}\)=\(\dfrac{2^{10}.3^8\left(1-3\right)}{2^{10}.3^8\left(1+5\right)}\)=\(-\dfrac{1}{3}\)

em dựa vào vd \(\dfrac{4^{16}}{2^8}\)= \(\dfrac{\left(2^2\right)^{16}}{2^8}=\dfrac{2^{16\cdot2}}{2^8}=2^4=16\)