2x+2-2x=96
=>2x.(22-1)=96
=>2x.3=96
=>2x=32
=>2x=25
=>x=5
7.2x=29+5.28
=>7.2x=28.(2+5)=
=>7.2x=28.7
=>2x=28
=>x=8
(x+7)2=7
=>\(x+7=\sqrt{7}\) hoặc \(x+7=-\sqrt{7}\)
=>\(x=\sqrt{7}-7\) hoặc \(x=-\sqrt{7}-7\)
\(2^{x+2}-2^x=96\)
\(\Rightarrow2^x.\left(2^2-1\right)=96\)
\(\Rightarrow2^x.3=96\)
\(\Rightarrow2^x=32=2^5\)
\(\Rightarrow x=5\)
Vậy : \(x=5\)
\(7.2^x=2^9+5.2^8\)
\(\Rightarrow7.2^x=2^8.\left(2+5\right)\)
\(\Rightarrow7.2^x=2^8.7\)
\(\Rightarrow2^x=2^8\)
\(\Rightarrow x=8\)
Vậy : \(x=8\)
\(\left(x+7\right)^2=7\)
\(\Rightarrow\left[\begin{array}{nghiempt}x+7=\sqrt{7}\\x+7=-\sqrt{7}\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=\sqrt{7}-7\\x=-\sqrt{7}-7\end{array}\right.\)
Vậy : \(\left[\begin{array}{nghiempt}x=\sqrt{7}-7\\x=-\sqrt{7}-7\end{array}\right.\)
