Đáp án cần chọn là: A

a,  2 x - 15 = 17

⇒ 2 x = 2 = 2 2 ⇒ x = 1

b,  7 x - 11 3 = 2 5 . 5 2 + 200

⇒ 7 x - 11 3 = 1000 = 10 3

⇒ 7x – 11 =10

⇒ 7x = 21

⇒ x = 3

......

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

Bài 1: 

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

=>7x-11=10

=>7x=21

hay x=3

huhuhuhu help me cứi tui

a,  x - 1 2 = 36

ó  x - 1 2 = 6 2

ó x – 1 = 6

ó x = 7

Vậy x = 7

b,  7 x - 11 3 = 2 5 . 5 2 + 200

=> 7 x - 11 3 = 800 + 200

=> 7 x - 11 3 = 1000

=> 7 x - 11 3 = 10 3

=> 7x – 11 = 10

=> 7x = 21

=> x = 3

Vậy x = 3

c,  x 11 = x

=> x 11 - x = 0

=> x ( x 10 - 1 ) = 0

=>

d,  x 2 = 2 3 + 3 2 + 4 3

=>  x 2 = 81

=> x = 9

e,  2 x 3 3 2 = 48

=>  2 x 3 9 = 48

=>  2 x 3 = 48 . 9

=>  x 3 = 216

=>  x 3 = 6 3

=> x = 6

f,  2 x + 1 3 = 125

=> 2 x + 1 3 = 5 3

=> 2x + 1 = 5

=> 2x = 4

=> x = 2

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

=>\(\left(x-1\right)^x\cdot\left[\left(x-1\right)^2-1\right]=0\)

=>\(x\left(x-1-1\right)\cdot\left(x-1\right)^x=0\)

=>x(x-2)(x-1)^x=0

=>x=0;x=2;x=1

2: \(\Leftrightarrow\left(6-x\right)^{2003}\left(x-1\right)=0\)

=>6-x=0 hoặc x-1=0

=>x=6;x=1

3: =>(7x-11)^3=32*25+200=1000

=>7x-11=10

=>7x=21

=>x=3

4: =>x^2-1=-3 hoặc x^2-1=3

=>x^2=-2(loại) hoặc x^2=4

=>x=2 hoặc x=-2

\(\left(7x-11\right)^3=2^5\cdot5^2+200\cdot2023^0\\ \left(7x-11\right)^3=32\cdot25+200\cdot1\\ \left(7x-11\right)^3=1000\\ \left(7x-11\right)^3=10^3\\ 7x-11=10\\ 7x=21\\ x=\dfrac{21}{7}=3\)

Lời giải:

$(7x-11)^3=2^5.5^2+200.2023^0=32.25+200=1000=10^3$

$\Rightarrow 7x-11=10$

$\Rightarrow 7x=21$

$\Rightarrow x=3$