Mũ cụ thể như thế nào vậy bạn? 

5.3^x+6 là $5.3^{x+6}$ hay $5.3^x+6$? 

2.5^5+3 là $2.5^{5+3}$ hay $2.5^5+3$??

x+6 là mũ nha

c, \(5^{x+4}-3\cdot5^{x+3}=2\cdot5^{11}\)

\(\Leftrightarrow5^{x+3}\cdot5-3\cdot5^{x+3}=2\cdot5^{11}\)

\(\Leftrightarrow5^{x+3}\left(5-3\right)=2\cdot5^{11}\)

\(\Leftrightarrow5^{x+3}\cdot2=2\cdot5^{11}\)

\(\Leftrightarrow5^{x+3}=5^{11}\)

\(\Leftrightarrow x+3=11\)

\(\Leftrightarrow x=8\)

Vậy x = 8

d, \(2^x+2^{x+1}+2^{x+2}+2^{x+3}+2^{x+4}+2^{x+5}=480\)

\(\Leftrightarrow2^x\left(1+2+2^2+2^3+2^4+2^5\right)=480\)

\(\Leftrightarrow2^x\cdot63=480\)

\(\Leftrightarrow2^x=\frac{160}{21}\)

\(\Leftrightarrow x\approx2,93\)

bạn nào chơi ff ko?

Xem lại đề ! 

Is there anything wrong with this topic?

5.3^x = 5.3⁴

=> x = 4

5.3⁴ = 7.3⁵ - 2.3⁵

       = 3⁵ . (7 - 2)

       = 5. 3⁵

  => 3^x = 3⁵

=> x = 5

\(6^2-\left(x+3\right)=45\)

\(36-\left(x+3\right)=45\)

\(x+3=35-45\)

\(x+3=-10\)

\(x=-13\)

lớp 6 mà bạn

a) \(2^2.3^{3x}-27^x=9^5\)

\(4.3^{3x}-\left(3^3\right)^x=\left(3^2\right)^5\)

\(4.3^{3x}-3^{3x}=3^{10}\)

\(3^{3x}\left(4-1\right)=3^{10}\)

\(3^{3x}.3=3^{10}\)

\(3^{3x+1}=3^{10}\)

3x + 1 = 10

3x = 9

x = 3.

b. \(5.3^x=135\)

\(3^x=27\)

\(3^x=3^3\)

x = 3.

c. \(5^x.5^4=5^{20}\)

\(5^{x+4}=5^{20}\)

x + 4 = 20

x  = 16

a: \(=\dfrac{-3}{5}\cdot\dfrac{5}{7}+\dfrac{-3}{5}\cdot\dfrac{3}{7}+\dfrac{-3}{5}\cdot\dfrac{6}{7}\)

\(=\dfrac{-3}{5}\left(\dfrac{5}{7}+\dfrac{3}{7}+\dfrac{6}{7}\right)=\dfrac{-3}{5}\cdot2=-\dfrac{6}{5}\)

b: \(=\dfrac{3}{13}\cdot\dfrac{6}{11}+\dfrac{3}{13}\cdot\dfrac{5}{11}-\dfrac{2}{13}=\dfrac{3}{13}-\dfrac{2}{13}=\dfrac{1}{13}\)

c: =>1/2x+1+3/8=7/16

=>1/2x=-15/16

=>x=-15/8

d: =>5/2x-1/3=1/6*(-9)/2=-9/12=-3/4

=>5/2x=-3/4+1/3=-9/12+4/12=-5/12

=>x=-1/6

cau b là sao bn

a) Đề:

<=> (2x - 17). 5⁶ = 5⁹

<=> 2x - 17 = 5⁹ : 5⁶

<=> 2x - 17 = 5³

<=> 2x - 17 = 125

<=> 2x = 142

<=> x = 71

Vậy x = 71

b) Đề:...........

<=> 3. x³ - 67 = 125

<=> 3. x³ = 192

<=> x³ = 64

<=> x = 4

Vậy x = 4

c) Đề:...........

<=> 5^{3x - 2} - 2. 125 = 125. 3

<=> 5^{3x - 2} - 250 = 375

<=> 5^{3x - 2} = 625

<=> 5^{3x - 2} = 5⁴

<=> 3x - 2 = 4

<=> 3x = 6

<=> x = 2

Vậy x = 2