Question

[Trần Long]

 

Answer 1

[Nguyễn Lê Phước Thịnh]

\(2^{x-3}-3\cdot2^x=-92\)

=>\(2^x\cdot\dfrac{1}{8}-3\cdot2^x=-92\)

=>\(2^x\left(\dfrac{1}{8}-3\right)=-92\)

=>\(2^x\cdot\dfrac{-23}{8}=-92\)

=>\(2^x=92:\dfrac{23}{8}=92\cdot\dfrac{8}{23}=4\cdot8=32=2^5\)

=>x=5

Answer 2

[Nguyễn Thị Thương Hoài]

2^{\(^{x-3}\)} - 3.2^\(x\)  = - 92

2\(^{x-3}\).(1 - 3.2³) = -92

2^{\(^{x-3}\)}. (-23) = -92

2^{\(^{x-3}\)}           = (-92) : (-23)

2^{\(^{x-3}\)}            = 4

2\(^{x-3}=2^2\)

\(x-3\) = 2

\(x=5\)

Vậy \(x=5\)