\(3.8^x-2.2^{3x}-16=0\)

Đề như thế này ạ

\(3.8^x-2.2^{3x}-16=0\)

\(\Leftrightarrow3.\left(2^3\right)^x-2.2^{3x}=16\)

\(\Leftrightarrow3.2^{3x}-2^{3x}=16\)

\(\Leftrightarrow2^{3x}\left(3-1\right)=16\)

\(\Leftrightarrow2^{3x}.2=16\)

\(\Leftrightarrow2^{3x+1}=2^4\)

\(\Leftrightarrow3x+1=4\)

\(\Leftrightarrow x=1\)

Vậy ....

\(3.8^x-2.2^{3x}-16=0\)

\(\Rightarrow3.8^x-2.8^x=16\)

\(\Rightarrow8^x\left(3-2\right)=16\Rightarrow8^x=16=8^2\)

Vì \(8\ne\pm1;8\ne0\) nên \(x=2\)

Vậy.......

Chúc bạn học tốt!!!

3x - 5.2.4 + 2.2³=0

3x-40+16=0

3x-24=0

3x=24

x=8

a. \(\left(2x-3\right)\left(x+1\right)+\left(2x-3\right)\left(3x-7\right)=0\)

\(\Leftrightarrow\left(2x-3\right)\left(x+1+3x-7\right)=0\)

\(\Leftrightarrow\left(2x-3\right)\left(4x-6\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}2x-3=0\\4x-6=0\end{matrix}\right.\)\(\Leftrightarrow x=\dfrac{3}{2}\)

b. \(\left(x-4\right)\left(3x-2\right)+x^2-16=0\)

\(\Leftrightarrow\left(x-4\right)\left(3x-2\right)+\left(x-4\right)\left(x+4\right)=0\)

\(\Leftrightarrow\left(x-4\right)\left(3x-2+x+4\right)=0\)

\(\Leftrightarrow\left(x-4\right)\left(4x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-4=0\\4x+2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-\dfrac{1}{2}\end{matrix}\right.\)

(2x-3)(x+1)+(2x+3)(3x-7)=0

<=> (2x-3)(x+1)-(2x-3)(3x-7)=0

<=> (2x-3)(x+1-3x+7)=0

<=> (2x-3)(-2x+8)=0

<=> 2x-3=0 => x=3/2

Hoặc -2x+8=0 => x= 4

Vậy x thuộc{3/2;4}

5.2^3x+1+2.2^3x+2 - 16 = 0

=> 5.2^3x.2+2.2^3x.2² =16

=> 2^3x ( 10 + 8)   = 16

=> 2^3x  = 16:18 = 8/9

=> x khong co gia tri

( x² - 4x + 16 )( x + 4 ) - x( x + 1 )( x + 2 ) + 3x² = 0

<=> x³ + 4³ - x( x² + 3x + 2 ) + 3x² = 0

<=> x³ + 64 - x³ - 3x² - 2x + 3x² = 0

<=> 64 - 2x = 0

<=> 2x = 64

<=> x = 32

( 8x + 2 )( 1 - 3x ) + ( 6x - 1 )( 4x - 10 ) = -50

<=> 2x - 24x² + 2 + 24x² - 64x + 10 = -50

<=> -62x + 12 = -50

<=> -62x = -62

<=> x = 1