Question

a) \(\dfrac{45^3.20^4.18^2}{180^5}\)

b)\(\dfrac{4^9.3^6+64^4}{16^4.100}\)

Bài 2: Tìm x

a)\(\left(2x+1\right)^3=27\)

b)\(3^{2x+1}.11=297\)

c)\(\left(7x-11\right)^3=2^5.5^2+200\)

d)\(\left(x-5\right)^4=\left(x-5\right)^6\)

Ngày mai đi học rùi, cần lắm

Answer 1

a.=\(\dfrac{4^3.9^3.5^44^4.18^2}{4^5.9^5.5^5}\)=\(\dfrac{4^4.9^2.2^2}{4^2.9^2.5}\)=\(\dfrac{4^2.2^2}{5}\)=\(\dfrac{64}{5}\)

Answer 2

Bài 2:

a) (2x+1)³ = 27

(2x+1)³ = 3³

=> 2x+1 = 3

=> 2x = 2

=> x = 1

Answer 3

b,\(=\dfrac{4^8.4.3^6+4^8.4^4}{4^4.4^4.4.25}\)=\(\dfrac{4^8\left(4.3^6+4^4\right)}{4^9.25}\)=\(\dfrac{4.3^6+4^4}{4.25}\)=\(\dfrac{4\left(3^6+4^3\right)}{4.25}\)=\(\dfrac{3^6+4^3}{25}\)=\(\dfrac{793}{25}\)

Answer 4

b,3^2x+1.11=297

\(\Rightarrow\)3^2x+1=297:11=27

\(\Rightarrow\)3^2x+1=3^3

\(\Rightarrow\)2x+1=3

\(\Rightarrow\)2x=3-1=2

\(\Rightarrow\)x=2:2=1

Answer 5

c,(7x-11)^3=1000

\(\Rightarrow\)(7x-11)^3=10^3

\(\Rightarrow\)7x-11=10

\(\Rightarrow\)7x=10+11=21

\(\Rightarrow\)x=21:7=3

Answer 6

d,(x-5)^4=(x-5)^6

\(\Rightarrow\)(x-5)^6-(x-5)^4=0

\(\Rightarrow\)(x-5)^4.\([\)(x-5)^2-1\(]\)=0

\(\Rightarrow\)\(\left[{}\begin{matrix}\left(x-5\right)^4=0\\\left(x-5\right)^2-1=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=5\\\left(x-5\right)^2=1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=5\\x=6\end{matrix}\right.\)

Answer 7

chúc bạn học tốt

tick cho mk nha!!!!

Answer 8

a, \(\dfrac{45^3.20^4.18^2}{180^5}\)

= \(\dfrac{5^3.9^3.4^4.5^4.9^2.2^2}{5^5.9^4.4^5}\)

= \(\dfrac{5^7.9^5.4^4.4}{5^5.9^5.4^4}\)

= \(\dfrac{5^7.9^5.4^5}{5^5.9^5.4^5}\)

= \(5^2=25\)