5.\(3^x\) = 8.3⁹ + 7.27³

5.\(3^x\) = 8.3⁹ + 7.(3³)³

5.\(3^x\) = 8.3⁹   + 7.3⁹

5.\(3^x\)  = 3⁹.( 8 + 7)

5.\(3^x\)  = 3⁹. 15

    \(3^x\) = 3⁹.15:5

     \(3^x\) = 3⁹.3

       \(3^x\)= 3¹⁰

        \(x\) = 10

Vậy \(x\) = 10 

Giải phương trình:

\(4x^2-9-\left(2x+3\right)\left(2x-1\right)=0\)

\(\Leftrightarrow\left(2x-3\right)\left(2x+3\right)-\left(2x+3\right)\left(2x-1\right)=0\)

\(\Leftrightarrow\left(2x+3\right)\left(2x-3-2x+1\right)=0\)

\(\Leftrightarrow\left(2x-3\right).\left(-2\right)=0\)

\(\Leftrightarrow2x-3=0\)

\(\Leftrightarrow x=\dfrac{-3}{2}\)

Vậy nghiệm của phương trình là \(x=\dfrac{-3}{2}\) .

\(x^3+x^2-4x=4\)

\(\Leftrightarrow x^3+x^2-4x-4=0\)

\(\Leftrightarrow x^2\left(x+1\right)-4\left(x+1\right)=0\)

\(\Leftrightarrow\left(x+1\right)\left(x^2-4\right)=0\)

\(\Leftrightarrow\left(x+1\right)\left(x-2\right)\left(x-2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+1=0\\x-2=0\\x+2=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=2\\x=-2\end{matrix}\right.\)

Vậy tập nghiện của phương trình là S= { -2; -1; 2}.

\(x^2\left(x^2+4\right)-x^2-4=0\)

\(\Leftrightarrow x^2\left(x^2+4\right)-\left(x^2+4\right)=0\)

\(\Leftrightarrow\left(x^2+4\right)\left(x^2-1\right)=0\)

\(\Leftrightarrow x^2-1=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-1=0\\x+1=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-1\end{matrix}\right.\)

Vậy phương trình có tập nghiệm là S= {-1; 1}.

\(\left(3x-3\right)^2=\left(x+5\right)^2\)

\(\Leftrightarrow\left(3x-3\right)^2-\left(x+5\right)^2=0\)

\(\Leftrightarrow\left(3x-3-x-5\right)\left(3x-3+x+5\right)=0\)

\(\Leftrightarrow\left(2x-8\right)\left(4x+2\right)=0\)

\(\Leftrightarrow2\left(x-4\right).2\left(2x+1\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-4=0\\2x+1=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=4\\x=\dfrac{-1}{2}\end{matrix}\right.\)

Vậy phương trình có tập nghiệm là S\(=\left\{\dfrac{-1}{2};4\right\}\) .

\(\left(2x-3\right)^2=\left(x+5\right)^2\)

\(\Leftrightarrow\left(2x-3\right)^2-\left(x+5\right)^2=0\)

\(\Leftrightarrow\left(2x-3-x-5\right)\left(2x-3+x+5\right)=0\)

\(\Leftrightarrow\left(x-8\right)\left(3x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-8=0\\3x+2=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=8\\x=\dfrac{-2}{3}\end{matrix}\right.\)

Vậy phương trình có tập nghiệm là S\(=\left\{\dfrac{-2}{3};8\right\}\) .

\(x^2\left(x-1\right)-\left(4x^2+8x-4\right)=0\)

\(\Leftrightarrow x^2\left(x-1\right)-4\left(x^2+2x-1\right)=0\)

\(\Leftrightarrow x^2\left(x-1\right)-4\left(x-1\right)^2=0\)

\(\Leftrightarrow\left(x-1\right)\left[x^2-4\left(x-1\right)\right]=0\)

\(\Leftrightarrow\left(x-1\right)\left(x^2-4x+4\right)=0\)

\(\Leftrightarrow\left(x-1\right)\left(x-2\right)^2=0\)

\(\Leftrightarrow x-1=0\)

\(\Leftrightarrow x=1\)

Vậy nghiệm của phương trình là x=1.

(\(27^{10}-5.81^4.3^{12}+4.9^8.3^8\)):\(\left(41.3^{24}\right)\)

\(=\left[\left(3^3\right)^{10}-5.\left(3^4\right)^4.3^{12}+4.\left(3^2\right)^8.3^8\right]:\left(41.3^{24}\right)\)

\(=\left(3^{30}-5.3^{28}+4.3^{24}\right):\left(41.3^{24}\right)\)

\(=\left[3^{24}\left(3^6-5.3^4+4\right)\right]:\left(41.3^{24}\right)\)

\(=\left(3^{24}.328\right):\left(41.3^{24}\right)\)

\(=328:41=8\)

15: \(\Leftrightarrow\left\{x^2-\left[8^2-\left(25-24\right)^3-63\right]^3-48\right\}=1\)

\(\Leftrightarrow x^2-48=1\)

=>x=7 hoặc x=-7

a) 120 - 5 . ( x + 2 ) = 45

    5 . (x + 2) = 120 - 45

    5 . (x + 2) = 75 

         x + 2 = 75 : 5

         x + 2 = 15

              x = 17

b) ( 2.x - 3 )² = 49

  ( 2.x - 3 )² = 7² 

  ( 2.x - 3 ) = 7

   2x = 10

       x = 5   

a) (24+5x)7⁹=7⁴

24+5x = 7⁴:7⁹

24+5x = 1/16807

5x = 1/16807 - 24

5x = -23,99...05

x = -23,99...05 : 5

x = -4,7999881

b) 294-(7x-217) = 3⁸.3¹¹:3¹⁶+6²

=>  294-(7x-217) = 3^8+11-16 + 6²

 294-(7x-217) = 3³+6²

=>  294-(7x-217) = 63

7x-217 = 295-63

7x-217 = 232

7x = 232+217

7x = 449

x = 449:7

x  = 449/7

c) 9 < 3^x < 81

=> 3² < 3^x < 3⁴

=> x = 3

d) 3^x+3^x+1 = 36

=> 2.3^x+1 = 36

2.3^x = 36-1

2.3^x = 35

3^x = 35:2

3^x = 17,5

=> x vô nghiệm

THanh you bạn nha

1​) x = -1\(\frac{1}{2}\)

_​​2) x = \(\pm2\); x = -1

3) x = -1 ; x = 1 ; x = -2i ; x = 2i

4) x \(\approx-1,59385382059801\) ; x \(\approx0,405545399146862\); x \(\approx6,18830832902225\)

Kế​t quả​ rú​t gọ​n: Unknown!!!

_​​

*** \(\dfrac{15-x}{8}=\dfrac{x-23}{10}\)

\(\Rightarrow10\left(15-x\right)=8\left(x-23\right)\)

\(\Rightarrow150-10x=8x-184\)

\(\Rightarrow150+184=10x+8x\)

\(\Rightarrow18x=334\)

\(\Rightarrow x=\dfrac{167}{9}\)

*** \(\dfrac{1}{2}\left|2x-1\right|-3\dfrac{2}{5}=\left(-\dfrac{1}{2}\right).\left(2015\right)^0\)

\(\Rightarrow\dfrac{1}{2}\left|2x-1\right|-3\dfrac{2}{5}=\left(-\dfrac{1}{2}\right).1\)

\(\Rightarrow\dfrac{1}{2}\left|2x-1\right|-3\dfrac{2}{5}=\left(-\dfrac{1}{2}\right)\)

\(\Rightarrow\dfrac{1}{2}\left|2x-1\right|-3\dfrac{2}{5}=\left(-\dfrac{1}{2}\right)\)

\(\Rightarrow\dfrac{1}{2}\left|2x-1\right|=\left(-\dfrac{1}{2}\right)+3\dfrac{2}{5}\)

\(\Rightarrow\dfrac{1}{2}\left|2x-1\right|=\dfrac{29}{10}\)

\(\Rightarrow\left|2x-1\right|=\dfrac{29}{10}:\dfrac{1}{2}\)

\(\Rightarrow\left|2x-1\right|=\dfrac{29}{5}\)

\(\Rightarrow\left[{}\begin{matrix}2x-1=\dfrac{29}{5}\\2x-1=-\dfrac{29}{5}\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}2x=\dfrac{34}{5}\\2x=-\dfrac{24}{5}\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{17}{5}\\x=-\dfrac{12}{5}\end{matrix}\right.\)