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Bài 1: Tìm x

a) Ta có: \(\left(7x-11\right)^3=2^5\cdot5^2+200\)

\(\Leftrightarrow\left(7x-11\right)^3=32\cdot25+200=1000\)

\(\Leftrightarrow7x-11=10\)

\(\Leftrightarrow7x=21\)

hay x=3

Vậy: x=3

b) Ta có: \(720:\left(41-\left(2x-5\right)\right)=2^3\cdot5\)

\(\Leftrightarrow720:\left(41-2x+5\right)=8\cdot5=40\)

\(\Leftrightarrow-2x+46=18\)

\(\Leftrightarrow-2x=18-46=-28\)

hay x=14

Vậy: x=14

c) Ta có: \(2\cdot3^x=10\cdot3^{12}+8\cdot27^4\)

\(\Leftrightarrow2\cdot3^x=10\cdot3^{12}+8\cdot3^{12}\)

\(\Leftrightarrow2\cdot3^x=18\cdot3^{12}\)

\(\Leftrightarrow3^x=\dfrac{18\cdot3^{12}}{2}=9\cdot3^{12}\)

\(\Leftrightarrow3^x=3^2\cdot3^{12}=3^{14}\)

hay x=14

Vậy: x=14

A (7x-11)³=2⁵.5²+200

    (7x-11)³=800+200

    (7x-11)³=1000

    (7x-11)³=10³

    7x-11=10

     7x=10+11

     7x=21

       x=21:7

       x=3

B 720:(41-(2x-5))=2³.5

   720:(41-(2x-5))=40

             41-(2x-5)=720:40

             41-(2x-5)=18

                    2x-5=41-18

                    2x-5=23

                       2x=23+5

                       2x=28

                         x=28:2

                         x=14

 C 2.3^x=10.3¹²+8.27⁴

    2.3^x=10.3¹²+8.(3^3.4)

      2.3^x=10.3¹²+8.3¹²

      2.3^x=3¹².(10+8)

     2.3^x=3¹².18

        3^x=( 3¹².18):2

        3^x=3¹².9

        3^x=3¹² .3²

        3^x=3¹⁴

          3^x=14

        x=14

1)

a) 2x + 5 = 3⁴ : 3²

2x + 5 = 3²

2x + 5 = 9

2x = 9 - 5

2x = 4

x = 4 : 2

x = 2

b) (3x - 24).73 = 2.74

(3x - 24).73 = 148

3x - 24 = 148/73

3x = 148/73 + 24

3x = 1900/73

x = 1900/73 : 3

x = 1900/219

c) [3.(42 - x)] + 15 = 23.3

126 - 3x + 15 = 69

141 - 3x = 69

3x = 141 - 69

3x = 72

x = 72 : 3

x = 24

d) 126 + (132 - x) = 300

132 - x = 300 - 126

132 - x = 174

x = 132 - 174

x = -42

2)

a) 120 - (x + 55) = 60

x + 55 = 120 - 60

x + 155 = 60

x = 60 - 55

x = 5

b) (7x - 11).3 = 25.52 + 200

(7x - 11).3 = 1500

7x - 11 = 1500 : 3

7x - 11 = 500

7x = 500 + 11

7x = 511

x = 511 : 7

x = 73

c) 2x + 2x + 4 = 544

4x = 544 - 4

4x = 540

x = 540 : 4

x = 135

3) 

a) 10 + 2x = 49 : 47

10 + 2x = 49/47

2x = 49/47 - 10

2x = -421/47

x = -421/47 : 2

x = -421/94

b) 70 - 5(x - 3) = 45

5(x - 3) = 70 - 45

5(x - 3) = 25

x - 3 = 25 : 5

x - 3 = 5

x = 5 + 3

x = 8

c) 4 + 95 : x = 143 : 142 - 23

4 + 95 : x = -3123/142

95 : x = -3123/142 - 4

95 : x = -3691/142

x = 95 : (-3691/142)

x = -13490/3691

a)

 \(\left(2x-15\right)^5=\left(2x-15\right)^3\\ \Leftrightarrow\left(2x-15\right)^5-\left(2x-15\right)^3=0\\ \Leftrightarrow\left(2x-15\right)^3.\left[\left(2x-15\right)^2-1\right]=0\\ \Leftrightarrow\left[{}\begin{matrix}2x-15=0\\\left(2x-15\right)^2-1=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}2x-15=0\\\left(2x-15-1\right).\left(2d-15+1\right)=0\end{matrix}\right.\\\Leftrightarrow\left[{}\begin{matrix}2x-15=0\\2x-16=0\\2x-14=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\x=8\\x=7\end{matrix}\right. \)

b) \(\left(7x-11\right)^3=\left(-3\right)^2.15+208\\ \Leftrightarrow\left(7x-11\right)^3=343=7^3\\ \Leftrightarrow7x-11=7\\ \Leftrightarrow x=\dfrac{18}{7}\)

a/  => \(\dfrac{3}{5}.\dfrac{1}{x}=\dfrac{6}{25}\)

=> \(\dfrac{1}{x}=\dfrac{2}{5}\)

=> x = 5/2

b/ \(\Rightarrow2\left(x-\dfrac{1}{3}\right)=\dfrac{2}{15}\)

=> \(x-\dfrac{1}{3}=\dfrac{1}{15}\)

=> \(x=\dfrac{2}{5}\)

c/ => | x + 1| = 10/21

=> \(\left[{}\begin{matrix}x=-\dfrac{11}{21}\\x=-\dfrac{31}{21}\end{matrix}\right.\)

d/ => \(5x+5=6x-3\)

=> x = 8

(7x-11)³=2⁵.5²+200

=> (7x-11)³=800+200

=> (7x-11)³=1000

=> (7x-11)³=10³

=> 7x - 11 = 10

=> 7x = 21

=> x = 3

(2x-15)⁵=(2x-15)³

=> (2x-15)⁵ - (2x-15)³ = 0

=> (2x-15)³ . [ (2x-15)² - 1 ] = 0

=> \(\orbr{\begin{cases}\left(2x-15\right)^3=0\\\left(2x-15\right)^2-1=0\end{cases}\Rightarrow\orbr{\begin{cases}2x-15=0\\2x-15=1\end{cases}\Rightarrow}\orbr{\begin{cases}2x=15\\2x=16\end{cases}\Rightarrow}\orbr{\begin{cases}x=\frac{15}{2}\\x=8\end{cases}}}\)

Mà x thuộc N 

=> x = 8

(3x-5)¹⁰=(3x-5)⁹

=> (3x-5)¹⁰ - (3x-5)⁹ = 0

=> (3x-5)⁹ .[ (3x-5) - 1 ] = 0

=> \(\orbr{\begin{cases}\left(3x-5\right)^9=0\\\left(3x-5\right)-1=0\end{cases}\Rightarrow\orbr{\begin{cases}3x-5=0\\3x-5=1\end{cases}\Rightarrow}\orbr{\begin{cases}3x=5\\3x=6\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{5}{3}\\x=2\end{cases}}}}\)

Mà x thuộc N 

=> x = 2

a)(7x-11)^3=1000                

   (7x-11)^3=10^3

    7x-11     =10

    7x          =10+11=21

      x          =21:7=3

hi các bợn

a) 150- x = -9

x = 150 -(-9)

x=150+9

x=159

b)4 (x-3)=48

x-3=48÷4

x-3=12

x=12+3

x=15

25/7nha

b) x^10=1x

=> x=0 ; 1

c)(2x-15)^5=(2x-15)^3

=> (2x-15)^4 = (2x-15)^2

=> (2x-15)^2 =1

=> 2x-15=1

=> x=8