\((3.x-2^{4} ):7^3 =2.7^{4}\)

\(=>(3.x-16):7^{3} =2.7^{4}\)

\(=>3.x-16=2.7^{4}:7^{3}\)

\(=>3.x-16=2.7^{4-3}\)

\(=>3.x-16=2.7\)

\(=>3.x-16=14\)

\(=>3.x=14+16\)

\(=>3.x=30\)

\(=>x=30:3\)

\(=>x=10\)

\(\left(3x-2^4\right):7^3=\left(2.7\right)^4\)

\(\Rightarrow\left(3x-2^4\right)=2^4.7^4.7^3\)

\(\Rightarrow3x-2^4=2^4.7^7\)

\(\Rightarrow3x=2^4.7^7+2^4\)

\(\Rightarrow3x=2^4.\left(7^7+1\right)=16\left(7^7+1\right)\)

\(\Rightarrow x=\dfrac{16\left(7^7+1\right)}{3}\)

Câu 3 :

A = 7776 . 8 - 2.243. 64

A = 62208 - 31104

A = 31104

Câu 1 :

a) \(12^5=3^5.4^5\)

b) \(20^6=4^6.5^6\)

c) \(54^3=6^3.9^3\)

Câu 2 :

a) \(3.5^{55}=3.\left(5^5\right)^{11}\)

b) \(4.3^{816}=4.\left(3^{17}\right)^{48}\)

c) \(9.8.7^{6412}=9.8.\left(7^{28}\right)^{229}\)

dssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss

\(\left(3x-2^4\right).7^3=2.7^4\)

\(\Rightarrow\left(3x-2^4\right)=2.7^4:7^3=14\)

\(\Rightarrow\)\(3x=14+16=30\)

\(\Rightarrow x=30:3=10\)

Hưng à! xin lỗi nha! tui mắc cười quá! Nguyễn Huy Hưng trả lời câu hỏi của Nguyễn Dũng (Ông hiểu rồi chứ!)

a,(x-5)^2=25

(x-5)^2=5^2

=>x-5=5

x=5+5=10

Vậy x=10

b,(2x+1)^2=25

(2x+1)^2=5^2

=>2x+1=5

2x=6

x=6:2

x=3

Vậy x=3

c,(3x-2^4).7^3=2.7^4

3x-2^4=2.7^4:7^3=14

3x=16+14=30

x=30:3

x=10

Vậy x=10

d,2.3^x+3^2+x=891

sao ko ai trả lời vậy

tại nó khó quá

Vũ Hồng Linh bạn check lại bài đầu dùm =_=" 

\(\left[-\frac{1}{3}\right]^3\cdot x=\frac{1}{81}\)

\(\Leftrightarrow x=\frac{1}{81}:\left[-\frac{1}{3}\right]^3\)

\(\Leftrightarrow x=\frac{1}{81}:\left[-\frac{1}{27}\right]\)

\(\Leftrightarrow x=\frac{1}{81}\cdot(-27)=-\frac{1}{3}\)

\(\left[x-\frac{1}{2}\right]^3=\frac{1}{27}\)

\(\Leftrightarrow\left[x-\frac{1}{2}\right]^3=\left[\frac{1}{3}\right]^3\)

=> Làm nốt 

Mấy bài kia cũng làm tương tự

(- \(\dfrac{1}{3}\))³.\(x\) = \(\dfrac{1}{81}\)

          \(x=\dfrac{1}{81}\) : (- \(\dfrac{1}{3}\))³

          \(x\) =  - (\(\dfrac{1}{3}\))⁴ :(\(\dfrac{1}{3}\))³

           \(x=-\dfrac{1}{3}\)

Vậy \(x=-\dfrac{1}{3}\)