x=13
h nha lấy 16^8 : cho 64 ra kq rồi cho mũ 4 lên là dc k mik nha
\(64\cdot4^x=16^8\)
\(2^6\cdot2^{2x}=2^{32}\)
\(2^{6+2x}=2^{32}\)
=> 6 + 2x = 32
=> 2x = 26
=> x = 13
Tìm x :
64 . 4x = 168
<=> 43 . 4x = ( 42 )8
<=> 43 . 4x = 416
<=> 4x = 416 : 43
<=> 4x = 416-3
<=> 4x = 413
=> x = 13
Vậy x = 13
\(64.4^x=16^8\)
\(\Leftrightarrow4^3.4^x=\left(4^2\right)^8\)
\(\Leftrightarrow4^{3+x}=4^{16}\)
\(\Leftrightarrow3+x=16\)
\(\Leftrightarrow x=16-3\)
\(\Leftrightarrow x=13\)
Vậy ............