(X+Xx2):34=504

(Xx1+Xx2):34=504

Xx(1+2):34=504

Xx3      :34=504

Xx3           =504x34

Xx3           =17163

X              =17163:3

X               = 5721        cho mình nhé! chúc bạn học tốt

( \(x\) + \(x\) \(\times\) 2) : 34 =  504

(\(x\) \(\times\) 1 + \(x\) \(\times\) 2): 34 = 504

\(x\) \(\times\)( 1 + 2):34 = 504

\(x\) \(\times\) 3: 34 = 504

\(x\) \(\times\) 3 = 504 \(\times\) 34

\(x\)  \(\times\) 3 = 17136

\(x\)     = 17136: 3

\(x\)     = 5712

Ta có: 2. x +4.x+8.x=504

=> 14x = 504

=> x = 504 : 14

=> x = 36

tim 3 so co ma ban

x - 306 = 504

x = 504 + 306

x = 810

Đặt A = 2³ + 2⁴ + ... + 2^x

=> 2A = 2⁴ + 2⁵ + ... + 2^{x + 1}

Khi đó 2A - A = (2⁴ + 2⁵ + ... + 2^{x + 1}) - (2³ + 2⁴ + ... + 2^x)

          =>    A  = 2^{x + 1} - 2³ = 2^{x + 1} - 8

Khi đó 2³ + 2⁴ + ... 2^x = 504

<=> 2^{x + 1} - 8 = 504

=> 2^{x + 1} = 512

=> 2^{x + 1} = 2⁹

=> x + 1 = 9

=> x = 8

Vậy x = 8

a) x - 306 = 504

x = 504 + 306

x = 810

b) x + 254 = 680

x = 680 - 254

x = 426

Sửa đề : 

\(\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{x}+\frac{1}{x\left(x+1\right)}=\frac{504}{1009}\)

\(\Rightarrow\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{x}-\frac{1}{x+1}=\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{2}-\frac{1}{x+1}=\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{x+1}=\frac{1}{2}-\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{x+1}=\frac{1}{2018}\)

\(\Leftrightarrow x=2018-1\)

\(\Leftrightarrow x=2017\)

Vậy ...

Sửa đề  \(\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{x\left(x+1\right)}=\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+....+\frac{1}{x}-\frac{1}{x+1}=\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{2}-\frac{1}{x+1}=\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{x+1}=\frac{1}{2}-\frac{504}{1009}\)

\(\Leftrightarrow\frac{1}{x+1}=\frac{1}{2018}\)

\(\Leftrightarrow x=2017\)

x = 2017 nha bạn