(x - 2)²⁰ - (x - 2)¹⁸ = 0

=> (x - 2)¹⁸ [ (x - 2)² - 1 ] = 0 

=> (x - 2)¹⁸ = 0 => x - 2 = 0 => x = 2

hoặc (x - 2)² - 1 = 0 => (x - 2)² = 1 => x - 2 = 1 => x = 3

Vậy x = 2 ; x = 3

\(\left(\frac{2}{3}x-1\right)^2=25\)

\(\Rightarrow\left(\frac{2}{3}x-1\right)^2=5^2=\left(-5\right)^2\)

\(TH1:\frac{2}{3}x-1=5\)

           \(\frac{2}{3}x=5+1=6\)

           \(x=6:\frac{2}{3}=6.\frac{3}{2}=9\)

\(TH2:\frac{2}{3}x-1=-5\)

            \(\frac{2}{3}x=-5+1=-4\)

             \(x=-4:\frac{2}{3}=-4.\frac{3}{2}=-6\)

Vậy: \(x\in\left\{-6;9\right\}\)

a)\(x^{15}=x\Rightarrow x\in\left\{0;1\right\}\)                                            d)Là ý b

b)\(\left(2x+1\right)^3=125\\ \left(2x+1\right)^3=5^3\Rightarrow2x+1=5\\ 2x=4\\ x=2\)                       e)\(\left(x-3\right)^2=25\\ \Rightarrow\left(x-3\right)^2=5^2\\ \Rightarrow\hept{\begin{cases}x-3=5\Rightarrow x=8\\x-3=-5\Rightarrow x=-2\end{cases}}\)

c)\(\left(x-5\right)^4=\left(x-5\right)^6\\ \Rightarrow x-5\in\left\{0;1\right\}\Rightarrow x\in\left\{5;6\right\}\)

Rút gọn hả bạn ?

( 3x - 1 )² - 9( x - 1 )( x + 1 )

= 9x² - 6x + 1 - 9( x² - 1 )

= 9x² - 6x + 1 - 9x² + 9

= 10 - 6x

( 2x + 3 )( 2x - 3 ) - ( 2x - 1 )² - ( x - 1 )

= 4x² - 9 - ( 4x² - 4x + 1 ) - x + 1

= 4x² - x - 8 - 4x² + 4x - 1

= 3x - 9

2( x - 2y )( x + 2y ) + ( x - 2y )² + ( x + 2y )²

= [ ( x + 2y ) + ( x - 2y ) ]²

= [ x + 2y + x - 2y ]²

= ( 2x )² = 4x²

\(\left(\dfrac{2}{5}-3x\right)^2-\dfrac{1}{5}=\dfrac{4}{25}\)

\(\Rightarrow\left(\dfrac{2}{5}-3x\right)^2=\dfrac{4}{25}+\dfrac{1}{5}=\dfrac{9}{25}\)

\(\Rightarrow\left[{}\begin{matrix}\dfrac{2}{5}-3x=\dfrac{3}{5}\\\dfrac{2}{5}-3x=-\dfrac{3}{5}\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}3x=-\dfrac{1}{5}\\3x=1\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=-\dfrac{1}{15}\\x=\dfrac{1}{3}\end{matrix}\right.\)

a) x=5

b) x=3

c) x=2

d) x=7

+5

a.(3^2+4^2).x=10^2

(9+16).x     =100

25.x           =100

x                =100:25

x                =4

b.(x-5)^2       =81

x-5             =9

x                =9+5

x                =14

c.(2x+1)^3 = 343

2x+1          = 7

2x              =7-1

2x              =6

x                =6:2

x                = 3

(9+16).x=100

25.x=100

x=100:25

x=4

bích ngọc sai rồi nhé

lỗi mik nhầm \(\frac{-8}{27}\)thành \(\frac{-25}{9}\)nhé

a.\(\left(x+\frac{2}{3}\right)^2=\frac{25}{9}\)

\(\left(x+\frac{2}{3}\right)^2=\frac{5^2}{3^2}\)

\(\left(x+\frac{2}{3}\right)^2=\left(\frac{5}{3}\right)^2\)

\(\Rightarrow x+\frac{2}{3}=\frac{5}{3}\)

\(x=\frac{5}{3}-\frac{2}{3}\)

\(x=\frac{3}{3}\)

\(x=1\)

cau b ne ban

\(\left(2x-\frac{1}{2}\right)^3=\frac{-8}{27}\)

\(\left(2x-\frac{1}{2}\right)^3=\frac{-2^3}{3^3}\)

\(\left(2x-\frac{1}{2}\right)^3=\left(\frac{-2}{3}\right)^3\)

\(\Rightarrow2x-\frac{1}{2}=\frac{-2}{3}\)

\(2x=\frac{-2}{3}+\frac{1}{2}\)

\(2x=\frac{-4}{6}-\frac{3}{6}\)

\(2x=\frac{-7}{6}\)

\(x=\frac{-7}{6}\div2\)

\(x=\frac{-7}{6}\times\frac{1}{2}\)

\(x=\frac{-7}{12}\)

Oky roi do ban :)))