Question

Giúp em với mọi người ơi em cảm ơn ạ

Answer 1

a) \(2C=2^2+2^3+...+2^{101}\)

\(\Rightarrow C=2C-C=2^2+2^3+...+2^{101}-2-2^2-...-2^{100}=2^{101}-2\)

\(\Rightarrow2^{2x-1}-2=2^{101}-2\Rightarrow2x-1=101\Rightarrow2x=102\Rightarrow x=51\)

b) \(\Rightarrow3\left(x-2\right)+7⋮\left(x-2\right)\)

\(\Rightarrow\left(x-2\right)\inƯ\left(7\right)=\left\{-7;-1;1;7\right\}\)

\(\Rightarrow x\in\left\{-5;1;3;9\right\}\)