36 = 2² . 3²

72 = 2³ . 3²

ƯCLN(36; 72) = 2² . 3² = 36

Vì 72 chia hết cho 36 => ƯCLN(72,36) = 36

`2^(x+1)-2^x =32`

`2^x (2-1)=32`

`2^x * 1 =32`

`2^x=32/1=32`

`2^x=2^5`

`=> x=5`

2^x+1- 2^x = 32

2^x.2 - 2^x = 2⁵

2^x.(2-1) = 2⁵

2^x.1=2⁵

2^x = 2⁵

x = 5

=[1800 - ( 64 - 54 )³ ]:8 + 22

=   (1800 - 1000):8+22

=800:8+22

=100+22=122

\(5\cdot2^2+\left(x+3\right)=5^2\)

\(5\cdot4+\left(x+3\right)=25\)

\(20+\left(x+3\right)=25\)

\(x+3=25-20\)

\(x+3=5\)

\(x=5-3\)

\(x=2\)

5.\(2^2\)+(x+3)=\(5^2\)

=>5.4+x+3=25

=>x=25-3-20

=>x=2

Đặt A = 1 + 3 + 3² + ... + 3¹¹

3A = 3 + 3² + 3³ + ... + 3¹²

3A - A = ( 3 + 3² + 3³ + ... + 3¹² ) - ( 1 + 3 + 3² + ... + 3¹¹ )

2A = 3¹² - 1

A = \(\dfrac{3^{12}-1}{2}\)

\(7.3^x+20.3^x=3^{25}\)

\(\Leftrightarrow3^x.27=3^{25}\)

\(\Leftrightarrow3^x=3^{25}:3^3\)

\(\Leftrightarrow x=22\)

( 7 + 20 ) .3^x = 3²⁵

27 . 3^x = 3²⁵ 

3³ . 3^x = 3²⁵

      3^x = 3²⁵ : 3³ 

      3^x = 3^25-3

      3^x = 3²²

=> x = 22

vậy x = 22

 8 + ( x - 9 ) = 125 - 64

8 + ( x - 9 ) = 61

x - 9 = 61 - 8

x - 9 = 53

x = 53 + 9

x = 62

vậy x = 62

\(2^3+x+3^2=5^3-4^3\)

\(\Leftrightarrow8+x+3^2=61\)

\(\Leftrightarrow x+3^2=53\)

\(\Leftrightarrow x=44\)

19 x 25 + 19 x 16 + 41

= 19 x (25 + 16) + 41

= 19 x 41 + 41

= (19 + 1) x 41

= 20 x 41

= 820

\(19\times25+19\times16+41\)

\(=19\times\left(25+16\right)+41\)

\(=41\times20=820\)

A = 8² : 4 . 3 + 2.5^2

A =  64 :4 .3 + 10.5

A = 16 .3 +50

A = 48 + 50

A = 98

= 64 : 4 . 3 + 2 . 25

= 16 . 3 + 50

= 48 + 50

= 98

x.(2x-1).(3x-126)=0

\(\Rightarrow\left[{}\begin{matrix}x=0\\2x-1=0\\3x-126=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{1}{2}\\3x=126\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{1}{2}\\x=42\end{matrix}\right.\)

X.(2X  - 1) .(3X - 126) = 0

X = 0 ;

2x- 1 =0  ⇒ x = 1/2

3x - 126 = 0

 x = 126: 3

x = 42