Đáp án C

a) Đặt: \(A=1+2^2+2^3+...+2^{10}\)

\(\Rightarrow2A=2\left(1+2^2+2^3+...+2^9+2^{10}\right)\)

\(\Rightarrow2A=2+2^3+2^4+...+2^{10}+2^{11}\)

\(\Rightarrow2A-A=\left(2+2^3+2^4+...+2^{10}+2^{11}\right)-\left(1+2^2+2^3+...+2^{10}\right)\)

\(\Rightarrow A=\left(2^3-2^3\right)+\left(2^4-2^4\right)+...+\left(2-1\right)+\left(2^{11}-2^2\right)\)

\(\Rightarrow A=0+0+...+1+\left(2^{11}-2^2\right)\)

\(\Rightarrow A=1+2^{11}-2^2=1+2048-4=2045\)

Vậy: \(1+2^2+2^3+...+2^{10}=2045\)

b) 

a] \(60-3\left(x-1\right)=2^3\cdot3\)

\(\Rightarrow60-3\left(x-1\right)=24\)

\(\Rightarrow3\left(x-1\right)=36\)

\(\Rightarrow x-1=12\)

\(\Rightarrow x=13\)

b] \(\left(3x-2\right)^3=2\cdot2^5\)

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

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

\(\Rightarrow3x-2=2^2\)

\(\Rightarrow3x=6\)

\(x=2\)

c] \(5^{x+1}-5^x=500\)

\(\Rightarrow5^x\left(5-1\right)=500\)

\(\Rightarrow5^x\cdot4=500\)

\(\Rightarrow5^x=125\)

\(\Rightarrow5^x=5^3\)

\(\Rightarrow x=3\)

d] \(x^2=x^4\)

\(\Rightarrow x=x^2\)

\(\Rightarrow x-x^2=0\)

\(\Rightarrow x\left(1-x\right)=0\)

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

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

giúp mình đi các bạn

\(\left(5x-29\right)-\left(2x-29\right)=-21\)

\(5x-29-2x+29=-21\)

\(5x-2x=-21+29-29\)

\(3x=-21\)

\(x=-7\)

`3/4+2/5x=29/60`

`2/5x=29/60-3/4`

`2/5x=-4/15`

`x=-4/15:2/5`

`x=-2/3`

Bài 1:

29.(85-47)+85.(47-29)

=29.38+85.18

=1102+1530

 =2632

BÀI 2

a, 15x = -75

        x =( -75) : 15

        x = -5

Vậy x= -5                                                            

b,-5x+8=-27

     -5x    = -27 - 8 

       -5x= -35

          x =-35 : -5

           x = 7

Vậy x = 7

c,3.(17 + x ) = - 42

       17 + x     = - 42 : 3

         17 + x    = -14

                x      = - 14 - 17

                 x = -31

Vậy x = - 31

d,-10 -( 2x -16) = 0

           2x - 16 = 10-0

           2x - 16 = 10

            2x = 10 +16

             2x = 26

                 x = 26 : 2

                  x = 13

 Vậy x = 13

e,( mik ko bít làm)

f,( tự làm nghen bạn)

a, = x² - 6x + 9 - 1 = (x - 3)² - 1² = (x - 4)(x - 2)

b, = 4x² - 4x - 3x + 3 = 4x(x - 1) - 3(x - 1) = (x - 1)(4x - 3)

c, = (x + 2)(5x - 4)

d, = 5x² - 5x + 2x - 2 = 5x(x - 1) + 2(x - 1) = (x - 1)(5x + 2)

a) \(x^2-6x+8\)

\(=x^2-4x-2x+8\)

\(=x\left(x-4\right)-2\left(x-4\right)\)

\(=\left(x-4\right)\left(x-2\right)\)

b) \(4x^2-7x+3\)

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

\(=4x\left(x-1\right)-3\left(x-1\right)\)

\(=\left(x-1\right)\left(4x-3\right)\)

c) \(\left(3x-1\right)^2-\left(2x-3\right)^2\)

\(=9x^2-6x+1-\left(4x^2-12x+9\right)\)

\(=9x^2-6x+1-4x^2+12x-9\)

\(=5x^2+6x-8\)

\(=5x^2+10x-4x-8\)

\(=5x\left(x+2\right)-4\left(x+2\right)\)

\(=\left(x+2\right)\left(5x-4\right)\)

d) \(5x^2-3x-2\)

\(=5x^2-5x+2x-2\)

\(=5x\left(x-1\right)+2\left(x-1\right)\)

\(=\left(x-1\right)\left(5x+2\right)\)

5x - x = 29 - 36 : 3

4x = 29 - 36 : 3

4x = 29 - 12

4x = 17

x = 17 : 4

x = 4,25