2.x.4=128
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\(4< 2^x< 128\Rightarrow2^2< 2^x< 2^7\) \(\Rightarrow2< x< 7\)

\(a,2^x.4=128\)
\(\Leftrightarrow2^x=128:4\)
\(\Leftrightarrow2^x=32\)
\(\Leftrightarrow2^x=2^5\)
\(\Rightarrow x=5\)
\(b,2^x=4.128\)
\(\Leftrightarrow2^x=2^2.2^7\)
\(\Leftrightarrow2^x=2^9\)
\(\Rightarrow x=9\)
\(c,3^x=3^3.3^5\)
\(\Leftrightarrow3^x=3^8\)
\(\Rightarrow x=8\)
\(d,2^x.\left(2^2\right)^3=\left(2^3\right)^2\)
\(\Leftrightarrow2^x.2^6=2^6\)
\(\Leftrightarrow2^x=2^6:2^6\)
\(\Leftrightarrow2^x=1\)
\(\Rightarrow x=0\)

\(^{2^x}.4=128\Rightarrow2^x=128:4\Rightarrow2^x=32=2^5\Rightarrow x=5\)


\(2^x.4=128\)
\(2^x.2^2=2^7\)
\(2^{x+2}=2^7\)
\(\Rightarrow x+2=7\)
x = 7 - 2
x = 5


(\(x\) - 5)2 = 16
(\(x-5\))2 = 42
\(\left[{}\begin{matrix}x-5=4\\x-5=-4\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=9\\x=1\end{matrix}\right.\)
Vậy \(x\) \(\in\) { 1; 9 }
B. 4\(x\) + 33 = 72
4\(^x\) + 33 = 49
4\(^x\) = 49 - 33
4\(^x\) = 16
4\(^x\) = 16
4\(^x\) = 42
\(x\) = 2
c. 2\(^x\).4 = 128
2\(^x\) = 128 : 4
2\(^x\) = 32
2\(^x\) = 25
\(x\) = 5
D, 5\(^x\) . 3 - 75 = 0
5\(^x\).3 = 75
5\(^x\) = 75: 3
5\(^x\) = 25
5\(^x\) = 52
\(x\) = 2
A) \(\left(x-5\right)^2=16=4^2\Rightarrow\left[{}\begin{matrix}x-5=4\\x-5=-4\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=9\\x=1\end{matrix}\right.\)
B) \(4^x+33=7^2\Rightarrow4^x=49-33\Rightarrow4^x=16=4^2\Rightarrow x=2\)
C) \(2^x.4=128\Rightarrow2^x=32=2^5\Rightarrow x=5\)
D) \(5^x.3-75=0\Rightarrow5^x.3=75\Rightarrow5^x=25=5^2\Rightarrow x=2\)

2x.4=128
2x =128:4
2x =32
x là cứ tính tứng số mủ 2 sao cho bằng 32
vì 32 bằng 25
nên x = 25

\(\left(4-x\right)^2+124=128\)
\(\Leftrightarrow\left(4-x\right)^2=4\)
\(\Leftrightarrow\left(4-x\right)^2=\left(\pm2\right)^2\)
\(\Leftrightarrow\orbr{\begin{cases}4-x=2\\4-x=-2\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=2\\x=6\end{cases}}\)
Vậy....
\(\left(4-x\right)^2+124=128\)
\(\left(4-x\right)^2=128-124\)
\(\left(4-x\right)^2=4\)
\(4-x=2\)
\(\Rightarrow x=2\)

\(a,2^x.4=128\\2^x.2^2=2^7\\ 2^x=\dfrac{2^7}{2^2}=2^{7-2}=2^5\\ Vậy:x=5\\ ----\\ b,\left(2x+1\right)^3=125=5^3\\ \Rightarrow 2x+1=5\\ 2x=5-1=4\\ x=\dfrac{4}{2}=2\\ ----\\ c,2x-2^6=6\\ 2x=6+2^6=6+64\\ 2x=70\\ x=\dfrac{70}{2}=35\\ ----\\ d,49.7^x=2401\\ 7^x=\dfrac{2401}{49}=49=7^2\\ Vậy:x=2\)
2.\(x\). 4 = 128
2\(x\) = 128 : 4
2\(x\) = 32
\(x\) = 32 : 2
\(x=16\)
Vậy \(x=16\)
2 . x . 4 = 128
2x = 128 : 4
2x = 32
x = 32 : 2
x = 16 .
Vậy x = 16 .