Question

Tim tat ca cac so tu nhien n sao cho:

a,2.16>_2n>4

b,9.27<_3n<_243

Answer 1

a) \(2.16\ge2n>4\)

\(\Rightarrow16\ge n>2\)

\(\Rightarrow n\in\left\{3;4;5;6;...;15;16\right\}\)

b) \(9.27\le3n\le243\)

\(\Rightarrow243\le3n\le243\)

\(\Rightarrow81\le n\le81\)

\(\Rightarrow n=81\)

Answer 2

a)\(2\cdot16\ge2n>4\)

\(\Rightarrow32\ge2n>4\)

\(\Rightarrow16>n>2\)

b)\(9\cdot27\le3n\le243\)

\(\Rightarrow243\le3n\le243\)

=>x rỗng