Question

Đã trả lời bởi chuyên gia

Answer 1

\[\begin{array}{l}
a,{\rm{ }}3x{\rm{ }} - {\rm{ }}2{\rm{ }} = {\rm{ }} - 6x{\rm{ }} + {\rm{ }}7{\rm{ }}\\
\Rightarrow 3x + 6x = 7 + 2\\
\Rightarrow 9x = 9\\
= > x = 1\\
vay:x = 1\\
B,{\rm{ }}{\left( {2x - 1} \right)^4} = {\rm{ }}81\\
\Rightarrow {\left( {2x - 1} \right)^4}{\rm{ = }}{\left( { \pm 3} \right)^4}\\
\Rightarrow \left[ \begin{array}{l}
2x - 1 = 3\\
2x - 1 = - 3
\end{array} \right.\\
\Rightarrow \left[ \begin{array}{l}
2x = 4\\
2x = - 2
\end{array} \right.\\
\Rightarrow \left[ \begin{array}{l}
x = 2\\
x = - 1
\end{array} \right.\\
{\rm{vay:S = \{ - 1;2\} }}\\
C,{\rm{ }}81{\rm{ }}:{\rm{ }}27x{\rm{ }} = {\rm{ }}{9^2}\\
dk:x \ne 0\\
\Leftrightarrow 3x = 81\\
\Leftrightarrow x = 27\left( {tm} \right)\\
vay:x = 27\\
D,{\rm{ }}0,5x{\rm{ }}.{\rm{ }}4x{\rm{ }} = {\rm{ }}{16^3}{\rm{ }}\\
\Leftrightarrow 2{x^2} = {16^3}\\
\Leftrightarrow {x^2} = 2048\\
\Leftrightarrow \left[ \begin{array}{l}
x = 32\sqrt 2 \\
x = - 32\sqrt 2
\end{array} \right.\\
vay:S = \{ 32\sqrt 2 ; - 32\sqrt 2 \} \\
E,{\rm{ }}3x{\rm{ }} - {\rm{ }}1{\rm{ }} = {\rm{ }}27.{\rm{ }}X - 2{\rm{ }}\\
\Leftrightarrow 27x - 3x = - 1 + 2\\
\Leftrightarrow 24x = 1\\
\Leftrightarrow x = \frac{1}{{24}}\\
vay:x = \frac{1}{{24}}\\
F,{\rm{ }}\frac{{{{16}^6}}}{{8x + 3}}{\rm{ }} = {\rm{ }}{4^9}{\rm{ }}\\
{\rm{dk:x}} \ne \frac{{ - 3}}{8}\\
\Leftrightarrow 8x + 3 = \frac{{{{16}^6}}}{{{4^9}}}\\
\Leftrightarrow 8x + 3 = 64\\
\Leftrightarrow 8x = 61\\
\Leftrightarrow x = \frac{{61}}{8}\left( {tm} \right)\\
vay:x = \frac{{61}}{8}\\
H,{\rm{ }}{\left( {{\rm{ }}2{\rm{ }} - {\rm{ }}3x{\rm{ }}} \right)^5} = {\rm{ }}32\\
\Leftrightarrow {\left( {2 - 3x} \right)^5} = {2^5}\\
\Leftrightarrow 2 - 3x = 2\\
\Leftrightarrow 3x = 0\\
\Leftrightarrow x = 0\\
vay:x = 0
\end{array}\]

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Answer 2

\[\begin{array}{l}
a,{\rm{ }}3x{\rm{ }} - {\rm{ }}2{\rm{ }} = {\rm{ }} - 6x{\rm{ }} + {\rm{ }}7{\rm{ }}\\
\Rightarrow 3x + 6x = 7 + 2\\
\Rightarrow 9x = 9\\
= > x = 1\\
vay:x = 1\\
B,{\rm{ }}{\left( {2x - 1} \right)^4} = {\rm{ }}81\\
\Rightarrow {\left( {2x - 1} \right)^4}{\rm{ = }}{\left( { \pm 3} \right)^4}\\
\Rightarrow \left[ \begin{array}{l}
2x - 1 = 3\\
2x - 1 = - 3
\end{array} \right.\\
\Rightarrow \left[ \begin{array}{l}
2x = 4\\
2x = - 2
\end{array} \right.\\
\Rightarrow \left[ \begin{array}{l}
x = 2\\
x = - 1
\end{array} \right.\\
{\rm{vay:S = \{ - 1;2\} }}\\
C,{\rm{ }}81{\rm{ }}:{\rm{ }}27x{\rm{ }} = {\rm{ }}{9^2}\\
dk:x \ne 0\\
\Leftrightarrow 3x = 81\\
\Leftrightarrow x = 27\left( {tm} \right)\\
vay:x = 27\\
D,{\rm{ }}0,5x{\rm{ }}.{\rm{ }}4x{\rm{ }} = {\rm{ }}{16^3}{\rm{ }}\\
\Leftrightarrow 2{x^2} = {16^3}\\
\Leftrightarrow {x^2} = 2048\\
\Leftrightarrow \left[ \begin{array}{l}
x = 32\sqrt 2 \\
x = - 32\sqrt 2
\end{array} \right.\\
vay:S = \{ 32\sqrt 2 ; - 32\sqrt 2 \} \\
E,{\rm{ }}3x{\rm{ }} - {\rm{ }}1{\rm{ }} = {\rm{ }}27.{\rm{ }}X - 2{\rm{ }}\\
\Leftrightarrow 27x - 3x = - 1 + 2\\
\Leftrightarrow 24x = 1\\
\Leftrightarrow x = \frac{1}{{24}}\\
vay:x = \frac{1}{{24}}\\
F,{\rm{ }}\frac{{{{16}^6}}}{{8x + 3}}{\rm{ }} = {\rm{ }}{4^9}{\rm{ }}\\
{\rm{dk:x}} \ne \frac{{ - 3}}{8}\\
\Leftrightarrow 8x + 3 = \frac{{{{16}^6}}}{{{4^9}}}\\
\Leftrightarrow 8x + 3 = 64\\
\Leftrightarrow 8x = 61\\
\Leftrightarrow x = \frac{{61}}{8}\left( {tm} \right)\\
vay:x = \frac{{61}}{8}\\
H,{\rm{ }}{\left( {{\rm{ }}2{\rm{ }} - {\rm{ }}3x{\rm{ }}} \right)^5} = {\rm{ }}32\\
\Leftrightarrow {\left( {2 - 3x} \right)^5} = {2^5}\\
\Leftrightarrow 2 - 3x = 2\\
\Leftrightarrow 3x = 0\\
\Leftrightarrow x = 0\\
vay:x = 0
\end{array}\]

Answer 3

Giúp mình cần gấp ạ ?????

Answer 4

C, 81 : 27x = 9²

Answer 5

E, 16⁶/ 8x + 3 = 4⁹

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