3ˣ⁺³ - 3ˣ⁺² = 162

3ˣ⁺².(3 - 1) = 162

3ˣ⁺².2 = 162

3ˣ⁺² = 162 : 2

3ˣ⁺² = 81

3ˣ⁺² = 3⁴

x + 2 = 4

x = 4 - 2

x = 2

mình giải ý c 

5(x+27)=200

(x+27)=200:5

(x+27)=40

x=40-27

x=13

(13.3^x-2-3^x):2=162

<=>3^x-2(13-3²)=162.2

<=>3^x-2.4=324

<=>3^x-2=324:4

<=>3^x-2=81=3⁴

<=>x-2=4

<=>x=6

Vậy...

Ta có: \(\left(13.3^{x-2}-3^x\right)\div2=162\)

\(\Leftrightarrow13.3^{x-2}-3^{x-2+2}=162.2\)

\(\Leftrightarrow13.3^{x-2}-3^2.3^{x-2}=324\)

\(\Leftrightarrow\left(13-9\right).3^{x-2}=324\)

\(\Leftrightarrow4.3^{x-2}=324\)

\(\Leftrightarrow3^{x-2}=\dfrac{324}{4}=81=3^4\)

\(\Leftrightarrow3^{x-2}=3^4\Leftrightarrow x-2=4\Leftrightarrow x=6\)

Vậy \(x=6\)

Ta có :

\(\left(13.3^{x-2}-3x\right):2=162\)

\(\Rightarrow3^{x-2}\left(13-3^2\right)=162.2\)

\(\Rightarrow3^{x-2}.4=324\)

\(\Rightarrow3^{x-2}=324:4\)

\(3^{x-2}=81\)

\(3^{x-2}=3^4\)

\(\Rightarrow x-2=4\)

\(x=4+2\)

\(x=6\)

Vậy \(x=6\) là giá trị cần tìm

~ Chúc bn học tốt ~

1/ ( x-3) ²=16

\(\Rightarrow\left[{}\begin{matrix}x-3=4\\x-3=-4\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=7\\x=-1\end{matrix}\right.\)

2/ (3x-1)³=8

\(\Rightarrow3x-1=2\\ \Rightarrow3x=3\\ \Rightarrow x=1\)

3/ (x-11)³=-27

\(\Rightarrow x-11=-3\\ \Rightarrow x=8\)

phần 4 mình ko rõ đề

4) \(x^3-3x^2+3x-1=-64\)

\(\Rightarrow x^3-3x^2+3x+63=0\\ \Rightarrow\left(x^3+3x^2\right)-\left(6x^2+18x\right)+\left(21x+63\right)=0\\ \Rightarrow x^2\left(x+3\right)+6x\left(x+3\right)+21\left(x+3\right)=0\\ \Rightarrow\left(x+3\right)\left(x^2+6x+21\right)=0\\ \Rightarrow\left[{}\begin{matrix}x+3=0\\x^2+6x+21=0\end{matrix}\right.\)

\(x+3=0\\ \Rightarrow x=-3\)

\(x^2+6x+21=0\\ \Rightarrow\left(x^2+6x+9\right)+12=0\\ \Rightarrow\left(x+3\right)^2+12=0\)

Vì \(\left(x+3\right)^2\ge0;12>0\Rightarrow\left(x+3\right)^2+12>0\Rightarrow x^2+6x+21vônghiệm\)

Vậy \(x=-3\)

a) 2.3^x=162

=> 3^x=162:2

=> 3^x=81

=> 3^x=3⁴

=> x=4

b) 3^x+3^x+2=810

=> 3^x+3^x.3²=810

=> 3^x.(3²+1)=810

=> 3^x=810:10

=> 3^x=81

=> 3^x=3⁴

=> x=4

2.3^x=162

  3^x= 162:2

  3^x= 81

 3^x= 3^4

=>  x=4

162:3^4=2

vậy x = 4

\(\dfrac{162}{3^x}=2\)

\(\Rightarrow3^x=\dfrac{162}{2}=81\)

\(\Rightarrow3^x=3^4\)

\(\Rightarrow x=4\)

162/3^x=2

=>3^x=162:2

=>3^x=81

=>3^x=3^4

=>X=4

vậy x=4

b: Ta có: \(x+3x-2=10\)

\(\Leftrightarrow4x=12\)

hay x=3